# Instruments and Equipment > Builders and Repair >  the demise of the pick guard

## Jim Nollman

A local Luthier is working on an F5 I recently purchased. He asked if I wanted him to build me an ebony pick guard which, since (he primarily builds guitars) to his eyes it seemed lacking. 

I told him that, because F5 mandolin strings sit so high off the body, I couldn't recall ever actually striking the body with a pick. 

However, my current working mandolin, has what luthier Ben Wilcox refers to as a "finger rest". It's basically a miniaturized floating pick guard. It's obvious that Ben spent some time designing it to stay completely away from the sound hole. I do use it as a finger rest, and have grown accustomed to planting my pinky on it while cranking out the notes. 

Today I did a little bit of research on the Mandolin Bros website, examining many mandolins to compare pickguards. I noticed that just about every mandolin built before the year 2000 has a pick guard, almost always big and plastic and to my eyes ugly. It made me wonder if anyone actually thinks its a good acoustic idea to feature a big piece of plastic blocking a sound hole? 

Almost all the instruments built after 2000 lack a pickguard. Of those newer instruments with pickguards, almost every example is consistently smaller than those prior to 2000. If the instrument is post 2000 and also handmade, the pick guard is almost always built of real wood. 

A lot of luthier's hang out here on the Cafe. I'm curious. Did you stop building pickguards because customers suddenly started declaring they didn't want them? Or was it an innovative builder's design choice, which soon spread to all the other builders?  

More to the point. Are these modern smaller pick guards currently designed to serve as finger rests? Or do you NOT make a distinction between pickguards and finger rests? 

I've decided for now, to forgo a finger rest on my new acquisition.

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## sunburst

Starting in about 1988 (pre 2000) or so, I've only put pick guards on mandolins at the customer's request. (They're all "finger rests" regardless of size, as I see it.)
When I started building mandolins, the usual process for players was to buy a mandolin with a big plastic pick guard, then take it off and leave holes in the instrument where the fasteners were. I figured if most people were going to take them off anyway, I'd just start them off without a pick guard and add one if they wanted it. That way, unused, unsightly hole is the mandolins are kept to a minimum. 
As for sound, there really doesn't seem to be much difference with or without a guard, but word had it (maybe still does?) that a guard blocking part of a sound hole is blocking sound. (I suppose they envision sound flowing forth straight out of the holes and crashing into the pick guard, maybe bouncing back and causing all manner of mayhem... I shudder to think..., but that's not how things work.)

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blindsay86, 

hank, 

Pete Jenner, 

Steve VandeWater

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## peter.coombe

I agree with John in that a pickguard does not seem to make any difference to the sound.  I always provide a pickguard, but it is smaller than the Gibson pickguards which I think are far too big.  My pickguards are made of wood to complement the woods of the mandolin.  Some people do remove them, but most people seem to keep them on.  If you going to allow other people to play your mandolin, then a pickguard is highly recommended, especially if it is a varnish finish.  Otherwise it doesn't really matter, and they can get in the way.

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## djweiss

I like having a pick guard on my mandolins...I don't plant my fingers on it, but it serves as a guide anyways.

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stevedenver

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## Rob Grant

All you need is for one player with long finger nails to plant their digit on that soft tonewood top and you'll see the need for a pickguard!<g>

Besides, pickguards don't have to be big, plastic and ugly...

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stevedenver, 

Timothy S

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## Steve Sorensen

As Rob indicates, as a builder, pick guards are cheap insurance for expensive finishes.  I've decided to include them unless requested otherwise to help keep those stabby pinky nails away from my carefully applied varnish and shellac tops . . . and they're attractive when not built to cover a quarter of the top!







Steve

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Avi Ziv, 

Barry Wilson, 

GrooverMcTube, 

j. condino, 

Jim Hudson, 

Mark Gunter, 

Sevelos, 

Stephen Porter, 

Timothy S

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## Charles E.

I like pick guards, here is one of mine. This is a flat top but I put one on arch tops too. I bend them on an Iron to have them closer to the body and give more pick clearence.

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blindsay86, 

bruce.b, 

hank, 

Sevelos

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## Charles E.

Here is an extreme example of the abuse a mandolin can suffer without one.

http://www.ebay.com/itm/Vintage-1942...item43b15246ae

This mandolin has been dicussed in the eBay forum

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## lenf12

....and more evidence of abuse. I think Andy's mando convinced Grisman to put the finger rest back on his own (much more expensive) mandolins. All of my mandolins have them as I can't play without 'em.

Len B.
Clearwater, FL

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Sevelos

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## Bernie Daniel

> ....and more evidence of abuse. I think Andy's mando convinced Grisman to put the finger rest back on his own (much more expensive) mandolins. All of my mandolins have them as I can't play without 'em.
> 
> Len B. Clearwater, FL


I like pickguard/finger rests as well -- I had a mini guard put on my Sam Bush as it with came without one of course.

That picture of Andy Statman is interesting -- he is a guy who can play the strings off a mandolin with very precise and accurate picking yet he still manages to carve a new graduations in the top while he plays!   :Smile:

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## lenf12

I think Andy has retired his snakehead and is now playing a Kimble F-5 (?) with a finger rest (of course). I can't perceive any sonic differences between a mandolin with or without the finger rest but the protection it provides to the finish is worth it to me. My mandolins have the big plastic Gibson style finger rests except for my Kentucky KM-340s (beater) which has an abbreviated ebony finger rest made by one of forum members. I don't plant my fingers when playing but I do lightly skim across the surface of the rest as a way to control the depth of the pick stroke. Works for me.  

Len B.
Clearwater, FL

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hank

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## barry

Statman's Kimble does not have a pickguard.  If this pic is recent,  the top is still fairly minty.  His technique may have changed over the years.  Or maybe the Kimble takes less work to get the music out.

http://www.brooklyndaily.com/assets/..._29_BK01_z.jpg

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## lenf12

Thanks for the picture Barry. That clears up my confused memory. ;-)

Len B.
Clearwater, FL

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## Paul Hostetter

> I think Andy's mando convinced Grisman to put the finger rest back on his own (much more expensive) mandolins. All of my mandolins have them as I can't play without 'em.


That's not quite how it worked. When Andy bought that A, he was Grisman's student. Grisman was of the opinion at the time (he's come around) that pickguards interfered with the sound, and urged him to get rid of it. Statman went ahead and played without it for many years until it looked like that photo. He says it was pristine when he bought it. At the Mandolin Symposium in 2006, the two had a rather spirited(!) back-and-forth onstage about that. Grisman went to some pains to tell the assembled that he'd long since seen the light about pickguards. By the next Symposium, Andy had sold the A and gotten the Kimble. 

Another thought about pickguards: Jody Stecher is another mandolinist from exactly that era and milieu who had the same idea about the sonic evils of pickguards. Sometime around 1972, at the San Diego Folk Festival, he borrowed my old A-1 for a mandolin workshop, but insisted he take the guard off - because it sounded soooo much better without it. I protested, but finally relented, telling him: one scratch and you're in the graveyard. So I'm sitting in the audience and one of the other participants is Carl Martin, of Martin, Bogan and Armstrong. He's up there and has no mandolin, so Jody generously and impulsively lent him mine. Martin, Bogan and Armstrong launched into a tune and every single downstroke, for the duration of the tune, was a swipe across the top that left a bare, shredded streak of raw spruce. By the end of the tune the top was absolutely mangled, a detail Carl Martin didn't even notice. Fully 25% of the finish on the top (not to mention a bunch of the spruce under it) was mechanically removed inside 3 minutes by one guy and a flatpick. All because of no pickguard. There are several morals to this story. I ended up having to refinish it of course, which I really don't like to do. Fortunately Jody and I are still good friends.

Here was Jody's issue as a player:



This is his Stan Miller, a profoundly great mandolin. The bare spot is from his trailing fingernails, because he often plays up the strings with the pick over the board. The pit was getting deeper and deeper, so I put this remedial guard on it:



It's on the surface covering the hole, not inlaid into it. It's worked great ever since.

A simpler thing to accomplish this end is a strategic patch of self-adhesive clear mylar. It's quite harmless, the adhesive can be loosened easily even many years later, and if youre careful, it will lay down on a smooth curved surface.

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ash89, 

brunello97, 

citeog, 

pjlama

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## Bernie Daniel

> ....Jody Stecher is another mandolinist from exactly that era and milieu who had the same idea about the sonic evils of pickguards. Sometime around 1972, at the San Diego Folk Festival, he borrowed my old A-1 for a mandolin workshop, but insisted he take the guard off - because it sounded soooo much better without it....


You were too nice of a guy....well in this case at least!  :Smile: 

If it were my mandolin, regardless of who wanted to borrow it the pick guard would have stay in place -- or the mandolin would have remained in its case.  One or the other.

Great story though -- I love those great  mandolin myths about hide glue, varnish, pick guard covers, red spruce, and the type of neck joint.....etc

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## Fretbear

That reminds me of the true (but even worse) story of Charley Derrington kindly loaning his dead-mint Loar to WSM to use for performance while Charley carefully labored over #73987. Bill returned it with a coffee cup-sized chunk of finish ground off the center of the back from his big spiky "Bluegrass Boys" belt buckle. Thanks, Charley!

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## Jim Nollman

So what I think I'm hearing here, is that pick guards are made necessary to protect against a specific and rather destructive picking technique, which is even favored by  some stellar players. This technique pushes the pick severely downward even as it pushes across the strings. And in fewer cases,  some of the same people who favor this instrument-destroying technique also favor instruments without a pickguard. 

Ah, too be so debonair about the basic tools of one's trade.  

In an odd sort of way, this wantonly dangerous technique reminds me of the conceptual art piece i once read about, where the artist had a collaborator shoot at him with a rifle as part of an art "happening" in a gallery. The .22 bullet  was supposed to miss the guy, barely, but the shooter's aim was askew, (maybe he also pushed down as he aimed) and it  nicked the artist in the arm. At the press conference the artist was bleeding quite a lot, but he tried his best to keep cool about it as if was simply the price of doing his art. 

I can't quite grok one of the stories here. OK. someone loans his instrument to a friend. The friend immediately pulls off the pickguard without even asking. Then, the friend lends the instrument he's just borrowed  to yet another player, also without asking permission. Then the second guy takes the stage, and immediately starts destroying  the mandolin with a picking technique  that clearly demands a pick guard.  AND...(this is where i suspend belief) the mandolin's owner watches it all happen, but doesn't intervene. 

Many thanks for sharing your thoughts about pickguards affecting tone and volume. Or Not. I had been hoping Dr Cohen would chime in here about the actual acoustics involved. 

Many more thanks for all your posted photos of finger rests/Pickguards. I especially like the design of the first one in the post by StevenS. I think I'll build something along the same lines. Not as a pickguard, but as a finger rest.

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## Ivan Kelsall

Well *Paul* - there's 'abbreviated' & then there's your 'Micro-guard'. A very smart remedy indeed !. I like the abbreviated style of pickguard,but the large Gibson style leaves me cold i'm afraid.When i bought my Lebeda,it had an abbreviated style guard on it,but i didn't like the shape. After seeing a pic.of a Tom Ellis guard,i re-shaped mine,put it back on & there it's staying as part of it's original build. Steve Sorenson's guards are the pinnacle of elegance (IMHO).Stunning to look at & funtional at the same time. I just wish mine had a bound edge to suit the mandolin,but it would possibly cost more than it's worth to get it done,
                                                                                                                                                                      Ivan

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## Paul Hostetter

Jody, true to his old days growing up with Grisman and Statman, didn't want a guard, so this was the best cure I could come up with, short of removing his other fingers that weren't needed for holding the pick. 

I personally like an elevated guard. Steve's really are superb.

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## Loudloar

The original poster commented on the demise of the pick guard, a.k.a. finger rest. As I look back over several decades I've seen the opposite trend. I see way more players today using finger rests. Back in the 1960's and 70's Bluegrass mandolin players generally did not want a finger rest. The consensus was that it hurt the sound, and after all, Bill didn't have one. I can tell you that on my 1924 F-5 there's no doubt that it dampens the E and A strings. I'm convinced that it's due to the weight attached to the end of the fingerboard rather than any blockage of the treble f-hole. Never the less, I reinstalled my finger rest several years ago. The difference in sound isn't huge and I think it looks cool.

The issue for modern builders is that it does add extra cost to the instrument, so they're inclined to include one only if it makes a difference in sales. I think we're seeing smaller finger rests due to a younger generation that's not so hooked on the traditional Gibson look.

Steve

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Hendrik Ahrend, 

stevedenver

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## billkilpatrick

> I can tell you that on my 1924 F-5 there's no doubt that it dampens the E and A strings. 
> Steve


i had a cheapie epiphone mm-30 with a pick-guard which might have been made around 2000.  i took it off and was alarmed to see it had been attached with one or two tiny screws! - can't remember.  i wouldn't put one on my current mandolin because of the (shudder) drilling.  i do notice pick marks, however.  might be the nitro-celluloid finish but a chamois and some elbow grease erases them easily.

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## billkilpatrick

> I can tell you that on my 1924 F-5 there's no doubt that it dampens the E and A strings. 
> Steve


interesting.  i had a cheapie epiphone mm-30 with a pick-guard which might have been made around 2000.  i took it off and was alarmed to see it had been attached with one or two tiny screws!  i wouldn't put one on my current mandolin because of the (shudder) drilling.  i do notice pick marks, however.  might be the nitro-celluloid finish but a chamois cloth and a little elbow grease erases them easily.

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## Jim Garber

I bought my Flatiron A5-2 in 1983 and it came without a pickguard/fingerrest. I called Steve and he quoted a price to make one. it was not unreasonable but I never had it made. As of today, it is prob my only mandolin that doesn't have one.

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## AlanN

I saw Aubrey Haynie play one time with a shortened guard on his mandolin, looked good. When I got my Gil, I had Charlie D. build one just like it, out of a special material. Had it on there for maybe a couple of months. Took it off, never put it back on. Have just gotten used to it without one.

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## Buck

> ...This technique pushes the pick severely downward even as it pushes across the strings...


In most cases, I don't think it's the pick that's doing the damage, at least not all of it.  It's the fingertips on the right and that are not holding the pick - pinky, ring and social fingers.

My fingers touch the top of the mandolin or pickguard there.  I keep my nails short and except for light scratches, have never come close to wearing through the finish, but I don't play as much as a pro either and my nitro finishes are tougher.  I touch a guitar top in the same way.  It's my point of reference.

FWIW, at least one of John Duffey's mandolins had small pick guard covering wear on the top.  It looked similar to the one PH showed on the JS mandolin above.

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stevedenver

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## almeriastrings

> When i bought my Lebeda,it had an abbreviated style guard on it,but i didn't like the shape. After seeing a pic.of a Tom Ellis guard,i re-shaped mine,put it back on & there it's staying as part of it's original build.


That is very well done, Ivan. Tasteful. How is the end closest to the bridge fixed? 

I like those 'abbreviated' guards myself.  That one is nicely proportioned.

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## StuartGold

This is a strange idea but my wife just got a new ebony chin rest for her violin and gave me her old one. I looked at it and suddenly I thought: if you could flatten the top curved area (chin area) and a bit of the bottom for  thickness, it would make a very nice pick guard. It would only be about 3" long but might work well if you're playing "off the coast of Florida" so to say. Has anyone heard of anyone doing this?

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## Paul Hostetter

I have, but...I wouldn't. No harm done in trying though. Well, actually, come to think of it, it'd be no good to a violinist again.  :Wink:

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Bill Baldridge

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## Capt. E

I've have come to the conclusion that most top wear comes from something other than the pick. Fingernails are the biggest offender. I saw one mandolin that had a spot about an inch in diameter worn through to the finish, above the bridge and realized it was exactly where the button is on a long-sleeve shirt. I'm even of the opinion that the big hole in Willie Nelson's guitar comes mostly from his finger nails, not his pick.  
Look at the molded black affair on a Lyon and Healy A...that is a finger rest, not a pick guard. It is very much equivalent to a chin-rest on a violin.  Let's stop calling them pick-guards.

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## Paul Hostetter

> I've have come to the conclusion that most top wear comes from something other than the pick. Fingernails are the biggest offender. I saw one mandolin that had a spot about an inch in diameter...


See my post #14 on the first page of this thread. 




> Look at the molded black affair on a Lyon and Healy A...that is a finger rest, not a pick guard. It is very much equivalent to a chin-rest on a violin.  Let's stop calling them pick-guards.


Can't join you on that one. Can't join you on adding a hyphen to the word chinrest either.

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BradKlein, 

Timbofood, 

xSinner13x

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## Capt. E

> See my post #14 on the first page of this thread. 
> 
> 
> 
> Can't join you on that one. Can't join you on adding a hyphen to the word chinrest either.


Well, I probably went a bit overboard comparing a violin chinrest with a pick guard, and the hyphen was unnecessary.   
It is interesting that recent instruments often lack a finger rest (pick guard) replaced by the latest "fad";the armrest (I admit to owning two of those). My favorite setup is an abbreviated pick guard with a McClung armrest. I also understand people removing pick guards because they do change the picking angle etc.   (I've probably misspelled several words)

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## Martian

> As Rob indicates, as a builder, pick guards are cheap insurance for expensive finishes.  I've decided to include them unless requested otherwise to help keep those stabby pinky nails away from my carefully applied varnish and shellac tops . . . and they're attractive when not built to cover a quarter of the top!
> 
> 
> 
> 
> 
> 
> 
> Steve


Steves, I love these mini guards, how do you attach? a friend epoxies 2 finish nails on the back, then drills 2 hols in fb extension, so they come on and off. Yours are beautiful

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## Steve Sorensen

Mike,
I use a single screw into the fingerboard support.  Since the Ebony bracket I use is shaped to fit up against the fingerboard support and under the fingerboard, the fingernail-guard stays quite well.
Steve

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## David Houchens

I fixed a hole that went all the way through at one point. He even wore down around the small end of the f hole. Maybe planting his pinkie in the hole?  Had to dish out the area and using blue carbon paper fit a piece of spruce to level it back.  I can't find a picture of the finished repair, but thinned a piece of ebony to around .030 and glued on top of the spruce patch. And told him to clip his nails. You can see in the picture where the finish has been applied and reapplied before he finally wore through.

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## Jim Garber

> I fixed a hole that went all the way through at one point. He even wore down around the small end of the f hole. Maybe planting his pinkie in the hole? Had to dish out the area and using blue carbon paper fit a piece of spruce to level it back.  I can't find a picture of the finished repair, but thinned a piece of ebony to around .030 and glued on top of the spruce patch. And told him to clip his nails. You can see in the picture where the finish has been applied and reapplied before he finally wore through.


Sorry, David... I am not sure who you are talking about. Who is "he"? Did I miss something?

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## pefjr

Pickguards change the tone negatively, and in some cases like the F2 lower the volume as well. The tail piece alters tone also. If there was a wooden tail piece made, preferably ebony,  I would replace the metal TP. Note:  This is IMO, don't ask for scientific data.

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## Dave Cohen

"Pickguards change the tone negatively,..."

Baloney.  Most pickguards are far enough above the soundhole(s) area that they don't affect the mass of air vibrating in the soundhole(s).  At most, the pickguard might affect the directional properties of the instrument's radiativity, but I have never seen (or heard) that.

"The tail piece alters tone also."

Maybe, but it depends more on mass than anything else.  A significant difference in mass at the tail end of the instrument can have some effect on (some of the) modal frequencies.  If you just swapped wood for metal,  you might or might not get the effect you want.  About 30 grams is about as light as mandolin tailpieces typically get.  There are metal tailpieces at that mass (e.g., conventional stamped, John Hamlett's, others?), and there are cast metal mandolin tailpieces with masses in excess of 80 grams.  While wood has a lower density, you have to use a greater volume of it to get a tailpiece that won't catastrophically self-destruct.  So you end up with a comparably heavy tailpiece.  Go ahead, ask me how I know that.

http://www.Cohenmando.com

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DavidKOS, 

Emmett Marshall, 

hank, 

Mark Gunter, 

Mike Bunting, 

Paul Hostetter, 

SlowFingers, 

Steve Sorensen

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## pefjr

> "Pickguards change the tone negatively,..."
> 
> Baloney.  Most pickguards are far enough above the soundhole(s) area that they don't affect the mass of air vibrating in the soundhole(s).  At most, the pickguard might affect the directional properties of the instrument's radiativity, but I have never seen (or heard) that.
> 
> "The tail piece alters tone also."
> 
> Maybe, but it depends more on mass than anything else.  A significant difference in mass at the tail end of the instrument can have some effect on (some of the) modal frequencies.  If you just swapped wood for metal,  you might or might not get the effect you want.  About 30 grams is about as light as mandolin tailpieces typically get.  There are metal tailpieces at that mass (e.g., conventional stamped, John Hamlett's, others?), and there are cast metal mandolin tailpieces with masses in excess of 80 grams.  While wood has a lower density, you have to use a greater volume of it to get a tailpiece that won't catastrophically self-destruct.  So you end up with a comparably heavy tailpiece.  Go ahead, ask me how I know that.
> 
> http://www.Cohenmando.com


Let me repeat my note for those that knee jerk without paying attention:


> Note: This is IMO, don't ask for scientific data


So, would you like a picture like this one:Based on my very own personal experience the volume picked up considerably when I removed the big ugly collectors obstacle covering the oval. Now take your baloney and make yourself a sandwich for lunch. Nice mando's BTW on your site. OK......geez...I'll make your day, ......How do you know that?

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j. condino

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## David Houchens

Jim, you didn't miss it. I didn't want to mention a name in case the spcm (society to prevent cruelty to mandolins ) was listening in.
 It's a rosewood Frailey (sp). There also a nice gouge through the scroll ridge which I guess is his upstroke with the pick. Lots of pick rash everywhere. Still a nice sounding mandolin.

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## David Houchens

Heres the pickguard/fingerguard and arm rest on my newest Possum Head mandolin. 
 The pickguard/ fingerguard is Madagascar RW and the armrest is Honduran RW. I didn't notice any difference in tone or volume but its been on most of the time. Plus, I hear some things one day and not another. Depends on how loud my ears are ringing. Or if I'm paying attention.


PS I think I posted this picture somewhere else, so excuse the duplicate.

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hank

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## chaz

I have the same Epiphone. What did you do after you removed the pickguard? Did you just leave the holes? If so, do the holes affect the sound? Are they really unsightly? 

Also, if  take it off, does it look like it is feasible to put it back on at a later date?

Thanks!

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## rf37

I am by no means an expert, nor do I claim to no much about effects of sound with or without pick guards (I will leave that up to those that know a little).  I do not have high dollar mandolins but the ones I do have I used my hard earned money to get them so to me they mean just as much.  However, Every mandolin I have had in the past did not have a guard...at the time I preferred it that way.  I recently bought a new Kentucky KM 505.  It had a guard....I asked during the order process if the pick guard was already installed and if it was not, then please leave it off.  They informed me that it was already mounted.  So I said ok.  I thought I would just take it off when I got it.  After the mandolin arrived...I played it and played it and am still playing it.  Idid not want to remove it until I was sure mandolin was a keeper.  I did not notice a difference in sound but I did notice a considerable difference in my hand position...so much so that my playing(which is not so good) was smoother and I had less right hand discomfort.  So now...I am not sure I will play without one ever again.  As far as the look....I always get truss rod covers custom built or as I did recently...build my own cover...so now I have the option to do the same with the pick guard.
So to make short story longer...I have grown to like my km505 pick guard included simply because it makes my pick'n more enjoyable for me and especially for those around me.  Iam now a member of "The pick guard camp"
rf37

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## Canoedad

Those big Gibson pick guards always remind me of 1970s ties.

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## DavidKOS

I'll offer a historical POV.

The instruments were originally designed as classical mandolins, and were most likely intended to be played with somewhat thinner picks, sitting, with the other instruments in all those pictures of the Gibson mandolin ensembles. No one was trying to play at maximum volume, except for stage performers. 

The pickguard does function as a finger rest in traditional pick holding methods, not firmly planting fingers but as a surface that allows the little finger of the hand to have a reference.

On archtop guitars I was taught to adjust the pickguard parallel to the plane of the strings and at the right level so the player is comfortable.

Now, Bluegrass mandolin comes along, and the instrument is used in another stylistic manner - the playing style is hard and aggressive, the tone color preferred is one of a hard pick and often played over the fingerboard extension (subject of many threads), and has to compete with a Scruggs-style banjo to be heard.

No wonder guys would resort to removing pickguards to have more access to the strings, and assuming that the pickguard also dampened some volume somehow.

Those makers on this thread that now offer pickguards as an option may have the right idea in terms of the market. 

If I were to order a new F style mandolin, I would want a full fretted extension and a pickguard - but many if not most other folks might prefer to have no extension or a scooped extension, and no pickguard.

The miniature pickguards seem like a good idea too.

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Timbofood

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## Mark Gunter

Seems strange to me that folk can be so adamant that covering or partially covering an f-hole has no effect on sound, cannot dampen sound, etc. It is a fact that objects between a source of sound and a listener provide interference to sound transmission, as it is a well known fact that sound is a mechanical phenomenon consisting of the movement of air in waves.

It would be impossible for a baffle to have _absolutely_ no effect. Perhaps most of the folk here mean to say that the pick guard/finger rest has no _appreciable_ effect on the sound. In which case this might hold true for the majority of listeners.

Note, the action of sound waves (pulsations of air) against a baffle, such as a pickguard, will necessary engender vibrations of the baffle material. The amount of damping that takes place with a baffle will depend partly on how well the baffle, which can act as a diaphram, responds to and transfers the vibration to the air surrounding it.

Maybe true that _no one_ can _ever_ hear a difference when a pick guard is removed or installed (though I highly doubt it) but this does not mean that its presence has no effect on the sound. That's baloney IMO.

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## Ken Waltham

I agree with your statement David, but, it may be even simpler. Monroe was a guy who didn't care much about anything but getting his music out there. His pickguard from a really fine condition ( when he bought it) 1923 F5 either came off, rattled, or whatever, and he just never put it back on. Early photos show it intact. He spawned a whole generation of imitators, and it became sort of a "Bluegrass thing" to do, because that's the way Bill did it. After all, you get more volume, right? Not at all.
The first Loar I ever played was David McLaughlin's. He handed it to me ( with pickguard intact) and said "some people think these decrease the volume, or something very close to that. He could get tons of volume, and, if anyone remembers them in their heyday, you could hear him approaching the mic from several feet away, as he played his lead in notes to a solo.
This is anecdotal evidence, I admit, but, I have never noticed a decrease in volume from a pickguard. And, as my buddy Tom once said, a Gibson without a p/g looks like a 50's Caddy with no fenderskirts.  :Smile:

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DavidKOS, 

sgarrity, 

Timbofood, 

Tobin

----------


## sunburst

> ...The first Loar I ever played was David McLaughlin's. He handed it to me ( with pickguard intact) and said "some people think these decrease the volume, or something very close to that...


Same here. Furthermore, he said that he had played the mandolin into the same mic, from the same distance, in the studio, with and without the pick guard, and there was no difference in the sound levels. So there's one more anecdote.

----------


## sunburst

> Seems strange to me that folk can be so adamant that covering or partially covering an f-hole has no effect on sound, cannot dampen sound, etc. It is a fact that objects between a source of sound and a listener provide interference to sound transmission, as it is a well known fact that sound is a mechanical phenomenon consisting of the movement of air in waves.
> 
> It would be impossible for a baffle to have _absolutely_ no effect. Perhaps most of the folk here mean to say that the pick guard/finger rest has no _appreciable_ effect on the sound. In which case this might hold true for the majority of listeners.
> 
> Note, the action of sound waves (pulsations of air) against a baffle, such as a pickguard, will necessary engender vibrations of the baffle material. The amount of damping that takes place with a baffle will depend partly on how well the baffle, which can act as a diaphram, responds to and transfers the vibration to the air surrounding it.
> 
> Maybe true that _no one_ can _ever_ hear a difference when a pick guard is removed or installed (though I highly doubt it) but this does not mean that its presence has no effect on the sound. That's baloney IMO.


In case you don't know this, Dave Cohen, who posted above (#37) can back up what he says with evidence from measurements of mandolin sound, and with experience as a luthier.
Respectfully, with what do you back up 
"...the action of sound waves (pulsations of air) against a baffle, such as a pickguard, will necessary engender vibrations of the baffle material. The amount of damping that takes place with a baffle will depend partly on how well the baffle, which can act as a diaphram, responds to and transfers the vibration to the air surrounding it" 
and related statements?

----------


## Jim Adwell

> Seems strange to me that folk can be so adamant that covering or partially covering an f-hole has no effect on sound, cannot dampen sound, etc. It is a fact that objects between a source of sound and a listener provide interference to sound transmission, as it is a well known fact that sound is a mechanical phenomenon consisting of the movement of air in waves.


The sound does not come out of the f-holes (or any other hole) on the top, it comes from the top itself.  Covering an opening loosely with a floating pickguard isn't any different than covering another part of the top.  

My own anecdotal experience suggests that a pickguard or the lack of one makes no hearable difference in the sound.  Even a plastic pickguard glued to a guitar top doesn't sound any different to me than an un-pickguarded top.

----------

Timbofood, 

Tobin

----------


## dang

> Respectfully, with what do you back up 
> "...the action of sound waves (pulsations of air) against a baffle, such as a pickguard, will necessary engender vibrations of the baffle material. The amount of damping that takes place with a baffle will depend partly on how well the baffle, which can act as a diaphram, responds to and transfers the vibration to the air surrounding it" 
> and related statements?


I thought he was describing a Virzi  :Wink:

----------


## colorado_al

I prefer not to have a pick guard since I don't plant a finger on the mandolin. I really like the look of some of the cutaway pick guards that don't cover the sound hole though. I saw this one on a 1980 Stiver #60

----------


## sgarrity

A pick guard is a requirement for me.

----------


## DavidKOS

> His pickguard from a really fine condition ( when he bought it) 1923 F5 either came off, rattled, or whatever, and he just never put it back on. Early photos show it intact. He spawned a whole generation of imitators, and it became sort of a "Bluegrass thing" to do, because that's the way Bill did it. )


Thanks!

I'm sure there is an interaction between the vibrating top, the air inside the and outside the mandolin, and the f holes would seem to also act like a port in a speaker. I wonder if any studies on f hole area have been done.

----------


## sunburst

> I wonder if any studies on f hole area have been done.


Yes, they have.

----------

DavidKOS

----------


## DavidKOS

> Yes, they have.


I was fairly certain that there were studies. If you have the links I'd love to see them - it would save a lot of time to know which are the right places to look. Thanks.

----------


## Tobin

> The sound does not come out of the f-holes (or any other hole) on the top, it comes from the top itself.  Covering an opening loosely with a floating pickguard isn't any different than covering another part of the top.  
> 
> My own anecdotal experience suggests that a pickguard or the lack of one makes no hearable difference in the sound.  Even a plastic pickguard glued to a guitar top doesn't sound any different to me than an un-pickguarded top.


Absolutely agree.  It is the entire top vibrating which creates the sound.  I think markscarts' statement on baffles is true enough in an academic sense, but the question here is whether a pick guard really qualifies as a baffle.  The f-holes are not like speakers, where sound emanates only from the holes themselves.  Thus, the pick guard partially blocking an f-hole is not really doing what "common sense" might suggest, in terms of blocking sound.  The f-holes are important in the quality/tone of the sound (as evidenced by the recent study on violin hole shapes), and apparently projection too, but volume didn't seem to be a factor.  At least, not in terms of whether it emanates from the holes themselves.  Their shape contributes to the volume and projection due to changing the overall vibration of the top, not as "speakers".

My first mandolin had no pick guard, and I got used to playing without one.  When I bought my Ellis, I didn't think I wanted a pick guard to be there.  I experimented with it on and off, trying to convince myself that it was reducing my volume.  But I couldn't tell any difference (non-scientific anecdote, but still...).  Eventually I kept it on there, and got used to it.  Now I have to have it on there.  What rf37 said in post #42 holds true for me as well.  It changed my hand position in a good way, and vastly improved my right hand technique.  I don't post on the guard, but I lightly brush my last two fingers across it, and it helps keep my hand more in-plane with the strings when picking.

----------

DavidKOS, 

Emmett Marshall, 

hank, 

Jim Adwell

----------


## JeffD

I always figured that if the pick guard had any appreciable effect (everything likely has some effect on everything), that effect was intended by the luthier, so removing the original pickguard was as much a modification of the original sound as adding one to an instrument built without.

As a result, I just keep it as is, with or without, as it came.

----------


## Dave Cohen

As is so often the case, many people post assumptions and even incorrect assertions, based on what appears to be "common sense", without ever consulting the scientific literature. It is as if because they don't know about existing work (and even well-established physics), it must not exist.  There are an awful lot of instances in which "common sense" is neither.

Regarding sound radiation from string instruments, there are two frequency regimes with different mechanisms of sound radiation.  In the low frequency regime, sound is radiated in two ways.  One is via "soundhole radiation", in which the main plate modes of motion interact (aka "couple") with the main air mode or "Helmholtz air resonance".  In the Helmholtz air resonance, air inside the instrument body cavity vibrates in its' first normal mode of motion, and that mode of motion serves as a spring for a "piston" of air vibrating in the soundhole region.  In practice, the amplitude of that motion is no more than about 3x to thickness of the top plate.  And, it is worth noting, the pickguards in most mandolins are well above the limits of the soundhole air piston's amplitude envelope.  The soundhole air piston in turn pushes air molecules outside that region, until the vibratory air motion eventually reached the listeners' ears.  The other mechanism is air motion outside the body of the instrument induced by the motion of the plates.  That mechanism is less prominent at low frequencies.  At higher frequencies, there isn't much soundhole radiation, but the second type (i.e., the outside-the-body stuff) comes into its own at high enough frequencies that the velocity of the plate motion is equal to or greater than the average velocity of the air molecules outside the body.  The take home is that the strength of the soundhole radiation is not affected at all by a pick guard over the hole, but the directional properties will be affected close to the instrument.  Further from the instrument (like no more than a meter away from the body), even the directional properties are not affected.  Further, the second (i.e., outside-the-body) mechanism is hardly affected at all by the presence or absence of a pick guard.

Some people in this thread wondered if there had been any work on this stuff.  As John Sunburst correctly pointed out, there certainly has been.  Some of it began in the mid 19th century with the works of Helmholtz and Savart, some in the early 20th century with the work of C.V. Raman, some in the mid 20th century with the work of Saunders, Hutchins, and others.  A whole lot of your questions are answered by the works of many of the Swedes and others at KTH in the 1960s -  1980s.

That is enough for now, although as you can surmise from the contents of my post, there is an awful lot more.

----------

Bertram Henze, 

Dale Ludewig, 

DavidKOS, 

Emmett Marshall, 

hank, 

Jim Adwell, 

Mark Gunter, 

Timbofood

----------


## DavidKOS

> As is so often the case, many people post assumptions and even incorrect assertions, based on what appears to be "common sense", *without ever consulting the scientific literature*. 
> .......
> Regarding sound radiation from string instruments, there are two frequency regimes with different mechanisms of sound radiation..... the pickguards in most mandolins are well above the limits of the soundhole air piston's amplitude envelope.  ....... The take home is that the strength of the soundhole radiation is not affected at all by a pick guard over the hole, *but the directional properties will be affected close to the instrument*.  Further from the instrument (like no more than a meter away from the body), even the directional properties are not affected. ....
> 
> .... Some of it began in the mid 19th century with the works of Helmholtz and Savart, some in the early 20th century with the work of C.V. Raman, some in the mid 20th century with the work of Saunders, Hutchins, and others.  A whole lot of your questions are answered by the works of many of the Swedes and others at KTH in the 1960s -  1980s.
> 
> That is enough for now, although as you can surmise from the contents of my post, there is an awful lot more.


I'd like to read the most recent stuff but am not even sure what to google.

Thanks for mentioning Helmholtz and Savart, et al.

The fact that the pickguard will affect the way sound radiates near the instrument would account for the anecdotal idea that the pickguard lowers volume.

----------


## sunburst

> ...If you have the links I'd love to see them...


Unfortunately, I don't have links saved anywhere, I'd have to look stuff up, and... what the heck, you can do that yourself!  :Smile: 
Start with the names Dave mentioned, and while you at it, check out some of his (Dave's) work too.

----------

Dale Ludewig, 

DavidKOS, 

hank, 

Timbofood

----------


## Timbofood

David brings up a very simple fact, read the old catalogs, they are NOT referred to as "pick guards", they are "finger rests".
When Bill's irritated him, for whatever reason, he just took it off. It has so little to do with volume, as other (far more learned than I) researchers have shared. 
That said, I can understand the desire to show the whole top, I also see the value in abbreviated size in finger rests. Personally, I would rather put "pinky ruts" in a finger rest than dig a "grave" in a fine, carefully chosen, piece of top wood.
Mine, has a full size, it's an early 70's Alvarez but, it feels right for me, I have had plenty of heads turn when I dig in. Just one mans opinion.

----------

DavidKOS

----------


## Phil Goodson

> Unfortunately, I don't have links saved anywhere, I'd have to look stuff up, and... what the heck, you can do that yourself! 
> Start with the names Dave mentioned, and while you at it, check out some of his (Dave's) work too.



Here's at least a starting point. Dr Cohen's paper has a bibliography that might help find other papers also.

----------

DavidKOS

----------


## Mandoplumb

Just a few rambling thoughts about pick guards finger rests or what ever you want to call them. Down thru the years I have played  with them if the mandolin had them without if it didn't. I won't get into the argument of If it dampens sound or not, I just thought if that little bit reduced volume or tone of the mandolin I weren't no count noway. As I got older I started having some trouble with my hands and need somewhere to rest it, whiteout a pick guard I rest  my hand on the bridge which I think dampens more than the pick guards so now if it don't have one I get one on it. I don't like the little ones, they seem like someone wearing a coat that is too small, it don't seem to fit. By the way I liked the wide ties, they went with my wide body.

Don't mean to poke fun at anyone but I laughed when I read the post about removing the pick guard and finding SCREWS held it on like screws into the mandolin was terrible, I wondered what was holding  his tuners on.

----------

Timbofood

----------


## mandroid

Flip side I added them when they didn't come with  one..

Only exception  my  flat top  D'Jangolin and the spruce topped Banjo Uke.

----------


## sblock

You want to know what REALLY dampens the sound?! Well, planting your pinky on the mandolin top (or heavily brushing your fingers against it) dampens the sound!  And pressing the mandolin against your belly on the back also dampens the sound!  A finger-rest ("pickguard") prevents the first thing from becoming a problem, but you can also avoid it by using a different playing technique, that is, never rest your pinky or brush your fingers on the top.  And a ToneGard prevents the second thing from becoming a problem, but you can avoid it by using a different playing technique, that is, never rest the mandolin against your body.  

But the fact is that many of us do not WANT to adopt a different playing technique!!  We find it awkward.  It can be helpful to plant, or to brush one's fingers, to provide a spatial reference for the right hand when picking. Or, as an anchor for tremolo, or for playing well away from the bridge.  A whole LOT of great players plant or brush, so it's not necessarily "bad" technique.  Furthermore, a whole LOT of great players hold the mandolin near their body, especially when they have to play standing up (e.g., onstage).  It's a much easier to use a ToneGard than to find a whole new playing position, at least for most of us. 

I say that pickguards and ToneGards are great things.  And so are armrests, while we're speaking about such things.  All these accessories exist for perfectly good reasons.  Not all of us take full advantage of them all, or even want them, but some of us certainly do.

----------


## Timbofood

No arm rest, no Tone Guard. Too cheap to buy something that learning some technique correction may (or may not) correct. I absolutely agree "they have their place" I will not argue that point. They are just not ones I see a requirement for me. Use anything which makes you feel comfortable and sound the way you want. More playing is better playing.

----------


## Mark Gunter

> Respectfully, with what do you back up
> "...the action of sound waves (pulsations of air) against a baffle, such as a pickguard, will necessary engender vibrations of the baffle material. The amount of damping that takes place with a baffle will depend partly on how well the baffle, which can act as a diaphram, responds to and transfers the vibration to the air surrounding it"
> and related statements?


Thank you, John. At this point, I might wish that I could reply that I have a formal education and many years of research in the subject to back it up, but I can't, and at any rate that shouldn't be necessary to exemplify my point. My formal education is in another realm. But I began studying (narrowly) molecular movement theory in my teens, and have studied wave theory and sonic theories enough for a casual acquaintance with the same. That type of education is not required to understand the effects of vibration on the air, and the mechanical effects of vibrating air against materials like sheets of wood, plastic and eardrums. I appreciate that asked with all respect. I would respectfully submit that luthier experience is not required to understand the physics, and also that being an experienced luthier does not confer upon one infallibility in opinions on the instrument or the craft. If such were the case, the many historical innovations we enjoy in instrument design, inasmuch as these have sometime been brought about by younger, less-experienced luthiers and dabblers throughout history, might not exist today.




> I thought he was describing a Virzi


dang, I may as well have been describing a virzi, because we are discussing a thin piece of wood, plastic, or other material suspended above a vibrating top. The obvious differences are that it is mounted to the exterior, and that whereas a virzi is assembled in such a way as to encourage its free vibration, a pick guard is assembled in such a way as to discourage it.

---------------------------




> The sound does not come out of the f-holes (or any other hole) on the top, it comes from the top itself. Covering an opening loosely with a floating pickguard isn't any different than covering another part of the top.


Jim, you make a very good point. I do not claim to be an expert here, and I've heard from some already who have indicated that I'm out of my league, and I have no argument for that. I am only making a sensible argument that items that are in the path of sound waves, which are mechanical pulsations of air, are "interference" items. I'm not stating that they make an "appreciable" difference, but I am stating my belief based on the physics involved that they do make a difference. The revered luthier, Dave Cohen, admitted to this when he wrote the following:




> At most, the pickguard might affect the directional properties of the instrument's radiativity, but I have never seen (or heard) that.


It should be intuitive for an educated person who understands how sound works and what baffles consist of to comprehend the possibility.

Once the possibility is understood, there comes the question of whether any interference is actually significant. I believe most of us would anecdotally answer, "No." I cannot detect any appreciable difference. That is where I find myself. My problem arises when I go on to say, "Since I can detect no appreciable difference, then NO ONE can detect it." To that I say, hogwash. Even if you were to test with an instrument, the sensitivity of which is far beyond the normal range of human hearing, you still cannot say that NO human can hear the difference. Therefore, it seems strange to me that folk can be so adamant about it. There have been some here who attest that they can hear the difference. Dave, and by extension John, say "Baloney." Well, OK, no more argument with you guys.

Finally, regarding the soundhole of an instrument, it has been said:




> The sound does not come out of the f-holes (or any other hole) on the top, it comes from the top itself.


Why does the top have sound holes in the front? Why are mutes placed as baffles in the soundholes effective? Do they merely restrict the top vibration due to contact with the top? Do they merely restrict the top vibration by stopping the free movement of air in and out of the top? Then, if air must flow in and out of the top in order for the soundboard to vibrate freely, does the air being "pumped" in and out of the top through sound holes itself make no sound waves? And finally, if "sound" (air vibrations) does not issue from the soundholes at all, why do we not place the holes elsewhere, like sides or back?

Or maybe rather than asking all these legitimate questions, I should ask how you are qualified to assert that sound does not issue from sound holes? Respectfully, of course.  :Wink:

----------


## Mark Gunter

Wow, sorry, I was responding to the second page and honestly hadn't noticed we were already two pages past that  :Redface: 

Having now read the third page, just want to say that I appreciate the explanation and the knowledge that Dave Cohen has shared on this page, it is very informative. Dave obviously knows a great deal about the subject.

----------


## DavidKOS

> You want to know what REALLY dampens the sound?! Well, planting your pinky on the mandolin top (or heavily brushing your fingers against it) dampens the sound!  .


I'm pretty sure that the way I was told that the finger rest works is that one barely touches it, it's there to provide a spatial reference not a support.

Although it is standard practice in BG banjo to plant the fingers when playing all those rolls.

----------


## Ivan Kelsall

From DavidKOS - _"Although it is standard practice in BG banjo to plant the fingers when playing all those rolls."_. Quite true David.One or two fingers can be rested on the banjo head,but they're rested there quite lightly,simply to provide a 'playing platform' for the picking fingers.The pressure from the fingers,is nothing compared to the pressure from the bridge & adds very little if any added pressure,certainly nothing you can hear.
     From David Cohen -_ "And, it is worth noting, the pickguards in most mandolins are well above the limits of the soundhole air piston's amplitude envelope."_. I won't pretend to understand 'absolutely' David's elloquent explanation - but i'll take that to mean that a pickguard covering a sound hole has little if any effect on the tone/volume of the instrument ?.
  I have to say that from an easthetic point of view,i rather like pickguards & it's only the cost of importing decent ones from the US that have prevented me from adding one to my Weber & Lebeda. The Lebeda has it's own rather 'annonymous' looking pickguard which adds nothing to the mandolin's appearance,hence it's consignment to the string compartment in it's case,
                                                                                                                                                                  Ivan

----------

DavidKOS

----------


## Petrus

I don't play as much as some folks (but every day), and I have never yet hit the top of the instrument with the pick, no matter how enthusiastically I am striking the strings.  The pick is always going laterally.  Does anyone routinely find themselves hitting either the pickguard or the top of the mandolin with the pick?  (I have seen old mandos with a lot of scratches and nicks on the top, so somebody must do it.)

One of these days I am going to buy that A type kit that doesn't have sound holes cut into it, and just assemble an A style mandolin with no sound holes, just to find out what it sounds like.  Should be interesting and I'll post the results eventually.  :Cool: 

https://www.internationalviolin.com/...out-fholes-cut

----------

Ivan Kelsall

----------


## Mandoplumb

> I don't play as much as some folks (but every day), and I have never yet hit the top of the instrument with the pick, no matter how enthusiastically I am striking the strings.  The pick is always going laterally.  Does anyone routinely find themselves hitting either the pickguard or the top of the mandolin with the pick?  (I have seen old mandos with a lot of scratches and nicks on the top, so somebody must do it.)
> 
> One of these days I am going to buy that A type kit that doesn't have sound holes cut into it, and just assemble an A style 
> mandolin with no sound holes, just to find out what it sounds like.  Should be interesting and I'll post the results eventually. 
> 
> https://www.internationalviolin.com/...out-fholes-cut


I don't think it will be interesting I think it will be dead. I have never built an instrument and claim no vast knowledge about same, but I have built speaker cabinets. The sound of the speaker is produced by the movemen of the paper or what ever the speaker is made of. The ports do not release the sound they allow air to be moved in and out of the enclosure, so the speaker does not have that resistance behind it. I would think the "sound holes" in an instruments would do the same thing allowing more freedom of movement for the top. That would also explain why a pick guard over a hole but not against the top would have no effect on the sound but a blockage of the hole like the mute as someone mentioned would. The mute is restricting the air movement and thus the freedom of the top  movement. I could be wrong but my limited knowledge and my logic says I'm right.

----------


## Rick Lindstrom

Human nature is so very interesting. What fascinates me about this discussion is the unfounded assumption we almost automatically make that a  large pick guard (or "finger rest") just has to have a bad effect on the sound. Since there is no evidence to support this contention, why not assume that the effect is positive instead?

This could extend to many of the "it has just got to be done this way to be right" facets of mandolin design and construction as well. Things we "know" to be "true" but have no evidence at all to support.

----------

DavidKOS

----------


## Tobin

> The sound of the speaker is produced by the movemen of the paper or what ever the speaker is made of. The ports do not release the sound they allow air to be moved in and out of the enclosure


Air doesn't really move in and out of the enclosure, either on a speaker or a mandolin.  If you put your hand in front of it, you're not going to feel a breeze blowing on it.  The opening just allows the air molecules to vibrate in a wave form, and for that wave form to have a continuous medium.  The molecules do move back and forth on a very small scale, but it is not air flow as some people tend to think.

The difference with a speaker is that the paper is starting the vibration of the air inside the enclosure, and needs an opening for the medium to be continuous to the outside world.  On a mandolin, the wood top is doing what the speaker paper element does.  It's already exposed to the outside world, worth a continuous medium to vibrate.  The sound holes just allow the vibration of the internal air of the mandolin (which is affected by the back plate as well, including all the effects of the waves bouncing around in there, producing overtones, etc.) to be released and affect the sound waves already produced by the vibrating top.

----------

DavidKOS, 

hank

----------


## Mandoplumb

Tobin I beg to differ if the music has a heavy bass and is loud you can feel air movement at the ports of speaker enclosures. I know the paper in a speaker is moving more than the top of a mandolin so the air movement would be much less and harder to impossible to detect but I think the principal is the same.

----------

DavidKOS

----------


## DavidKOS

Either way the speaker port analogy may be useful.

----------


## Mark Gunter

The speaker port analogy is a useful one, and the question then is that if the only reason for a sound hole is to act as a speaker port, and significant sound does not issue from the hole, why is the hole placed in front? The questions I've been asking are rhetorical ones. The answer is known. Sound does indeed issue from the sound holes. Also, Dave in his last reply offered a description with some details about _how_ the low frequency sounds issue from the sound hole, and cited literature about it.

----------


## Jim Adwell

It's entirely possible make an instrument with no top sound hole, with an opening or openings in the sides.  I've done this and so have others.  You could even put the opening on the back (been done, I think, but not by me), which raises the interesting possibility of varying the Helmholtz frequency of the instrument while you're playing it.  :Wink: 

Guitars with no front sound hole look quite odd, though.

EDIT: a picture is worth a thousand words...

----------


## sunburst

The speaker port analogy is an imperfect analogy. Speaker cones do not behave the same way mandolin tops behave, the speaker enclosure is designed to be as inert as possible, and the speaker cone is made to be the only moving part of the speaker as much as is possible. In the mandolin, the top, back, sides, and the rest of the instrument are free to move. A speaker cone is made to be light and as stiff as possible so that is moves as a unit in the frequencies dictated by the electrical signal that drives it. The mandolin top (and back and other parts) move in their normal modes of motion, not as units responding to a specific signal. I don't know enough about speakers to go much farther than this, but since the "box" that is the speaker is not doing the same thing and the "box" that is the mandolin, I must assume that the ports don't do exactly the same things in both cases.

As for position of the sound holes in a mandolin, it is not an important thing for them to be in the top. They can be in the sides or the back and the sound will be similar. Where they are in relation to the modes of motion of the air inside the mandolin can make a difference, however, and that is part of the difference in sound between oval hole mandolin and f-hole mandolins. F-holes in the back, in positions similar to the usual f-holes in the top, would probably sound more like f-holes in the top than an oval hole in the back would, if that's not too convoluted to follow.

As for the suggested experiment of building an A kit with no f-holes to see what it sounds like, it would be much less expensive and time consuming to simply cover the f-holes in an existing mandolin to see what it sounds like. That's been done by quite a few people, but it is an interesting thing to try so that we can get first hand experience in perceiving the sound difference.

----------


## Tobin

> Tobin I beg to differ if the music has a heavy bass and is loud you can feel air movement at the ports of speaker enclosures. I know the paper in a speaker is moving more than the top of a mandolin so the air movement would be much less and harder to impossible to detect but I think the principal is the same.


What you're feeling in front of a speaker is the air vibrating with the sound waves, but not flowing in one direction.  And to be fair, I wasn't implying that you were making the case that air flows in a constant directional movement.  But I think some people are under the mistaken impression that air somehow needs to flow out of the sound holes, and I think using the term air flow is a misnomer here, which exacerbates that misinterpretation.  

So back to the other thing I was trying to say.  The vibrating mandolin top is, essentially, the speaker cone that sets the air to vibrating, regardless of the sympathetic response of the sides and back.  So when we talk of speaker cones, what we should be asking is this:  do they put sound holes, in speaker cones,?

----------


## Mark Gunter

John, don't some people make mutes to go in their sound holes? I think I've see these, seems someone posted something recently about it, but my memory like many of my faculties is not what it used to be. I don't have time to search it now.

Edit for Tobin: 




> I think some people are under the mistaken impression that air somehow needs to flow out of the sound holes


If you're referring to any of my posts, you do have a mistaken impression of my intention about a stream of air flowing out of the sound holes. Air must pulse freely in and out of the sound hole, in miniscule amounts, to accommodate the motion of the vibrating top. A hermetically sealed box would resist vibrations of the top I think. There are reasons for the sound holes, and for their locations. There is reason behind the current accepted norms in instrument construction. There is a reason that some people put side "monitor" sound holes to face the player.

----------


## DavidKOS

> You could even put the opening on the back (been done, I think, but not by me), which raises the interesting possibility of varying the Helmholtz frequency of the instrument while you're playing it.


Brazilian berimbau players open and close the resonator gourd to change tone color, they hold the open end at varying places on their body thus changing the Helmholtz frequency.




> The speaker port analogy is an imperfect analogy. Speaker cones do not behave the same way mandolin tops behave........ I don't know enough about speakers to go much farther than this, but since the "box" that is the speaker is not doing the same thing and the "box" that is the mandolin, I must assume that the ports don't do exactly the same things in both cases.


I see your point, but in speaker design the port has more to do with tuning the overall response - more bass, less bass - than it does with volume. A sealed design cabinet works differently than a ported one.

From what I understand so far (and please correct me if it's wrong) the size of soundholes will affect the relative bass and treble response of a particular instrument, although some volume issues may be involved too depending on the design.

----------

Jim Adwell

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## sunburst

> John, don't some people make mutes to go in their sound holes? I think I've see these, seems someone posted something recently about it, but my memory like many of my faculties is not what it used to be. I don't have time to search it now.


That started as a way to control feedback when people started plugging acoustic instruments in so they can play really loud. As has been said, an instrument body will respond to any vibration/energy input by vibrating in it's normal modes of motion, and that includes the sound on stage. When a pickup is installed, that can quickly lead to feedback, so plugging the holes dampens the Helmholtz motion of the air in the box, and thus reduces feedback. That, intern, dampens the rest of the sound of the instrument because, as has been said, everything works together in a well made instrument to produce sound. That can become a liability when we start attaching pickups and playing loud with the help of amplification.






> ... There is reason behind the current accepted norms in instrument construction. There is a reason that some people put side "monitor" sound holes to face the player.


There is some amount of directional radiation from the sound hole, but it is lost more than... say, 3 feet from the instrument. Several casual "tests" have shown that the player hears a difference when there is a side port, but the audience does not. (It's similar to what Dave said about the pick guard. It might change the direction of sound radiation close to the instrument, but the effect is lost as we move further away.)

----------

DavidKOS

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## sunburst

> ...I see your point, but in speaker design the port has more to do with tuning the overall response - more bass, less bass - than it does with volume. A sealed design cabinet works differently than a ported one.
> 
> From what I understand so far (and please correct me if it's wrong) the size of soundholes will affect the relative bass and treble response of a particular instrument, although some volume issues may be involved too depending on the design.


It sort of does that indirectly. Changing the size of the port (sound hole/s) changes the frequency of the Helmholtz resonance, and that frequency can affect bass response because it affects coupling in the instrument. Coupling, in short, is interaction between the vibrating top plate, the vibrating back plate, and the vibrating air within the instrument (plus other things). Increasing or decreasing the size of the port (sound hole/s) is not a predictable way of "adjusting" bass or treble response in the instrument because the frequency of the main vibrational modes of the top and back can be very different from one instrument to the next, so lowering or raising the Helmholtz frequency may or may not change or improve bass response. It depends upon whether or not overall coupling in the instrument is improved. Good coupling leads to loudness and bass response. I'm not sure that coupling in a loudspeaker is similar. (As I said, I don't know as much about speakers as instruments.)
Also, the relationship between port size and Helmholtz frequency is not a direct relationship. It takes quite a large change in port size to make a small change in Helmholtz frequency.

I assume that speaker designers are interested in adjusting the Helmholtz frequency of the box by adjusting the port size, for best response over the speaker's range of frequencies, and that coupling with the modes of motion of the back, sides, and other parts of the enclosure is intended to be minimal, but I'm just guessing here because, once again, I don't really know much about speakers.

----------

DavidKOS, 

hank

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## Mandoplumb

Like I said when I started this I have limited to no knowledge about how a instrument produces sound. I see some very logical difference in the speaker cone and an instrument top but logically speaking they are both producing sound so I'm sure if we knew enough there are simularites. I know I'm using logic rather than science but isn't science logical? LOL

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## DavidKOS

> I'm not sure that coupling in a loudspeaker is similar.


It pretty much is, although as you note the overall dynamics are different with a mandolin.

I appreciate the comments.

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## JeffD

So the analogy I heard is like when you throw a rock in the center of a pond. The vibrations move out to the edges, but no single droplet of water makes the trek from the rock's disturbance to the edge of the pond. 

Pressure waves come off the front of the instrument, and some air might move in and out of the holes, but no piece of air flows from inside the instrument to your ear.

I think I have that right.

Something like that.

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## sblock

Mandoplumb is absolutely correct.  The air volume moved by a loudspeaker -- or a mandolin -- depends strongly on the frequency.  Deep bass notes move a lot more air, and they require vastly more energy to produce.  A good loudspeaker can blow out a candle placed in front of it, given the right input signal (this is a well-known demonstration, see here ).  A mandolin mostly produces high frequencies, however.  These involve moving comparatively smaller volumes of oscillating air. You cannot blow out a candle with a mandolin, and the boundary layer of larger air movements above the holes in the top does not extend more than a few mm.  At A = 440 Hz, the wavelength of the sound is about (340 m/s over 440 Hz = 0.77 m)  30 inches, so the sound is mainly DIFFRACTING, and not radiating in straight lines outward.  You need to get into the "far field," i.e., several meters away from the mandolin, before the sound field starts behaving that way. The fact is that a pickguard DOES NOT diminish the volume of the sound produced by a mandolin in any appreciable way in the far field. This is readily tested, and it is not a matter of subjective opinion. A pickguard _might_ be able to alter the sound that you hear very close in, _in principle_, but even that effect is exceedingly small.  It is overly simplistic and incorrect, from a physics perspective, for folks to write that a pickguard "blocks the sound projected from the ff-holes," or words to that effect.  First off, most of the sound does _not_ emerge from the ff-holes.  And second, the location of the pickguard (about a cm above the top) does not block the part of the sound that does. 

To paraphrase Mark Twain, I think that reports of the demise of the pickguard are being reported prematurely!

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DavidKOS, 

sunburst, 

Timbofood

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## Mark Wilson

> The fact is that a pickguard DOES NOT diminish the volume of the sound produced by a mandolin in any appreciable way in the far field.... It is overly simplistic and incorrect, from a physics perspective, for folks to write that a pickguard "blocks the sound projected from the ff-holes," or words to that effect.


Sounds right to me.  But, I'd still might add "unless you believe otherwise" to the end of any audio argument. When the audio difference is small or not at all, what you believe is what you tend to hear imo.

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## sblock

> Sounds right to me.  But, I'd still might add "unless you believe otherwise" to the end of any audio argument. When the audio difference is small or not at all, what you believe is what you tend to hear imo.


If I'm not mistaken, that's known as the "placebo effect." It is very strong in the audiophile community.

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## Bertram Henze

> "placebo effect."


I wonder if it isn't related to auditory pareidolia. Long before supermarkets replaced the djungle, it was safe to hear the tiger before it heard you.

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## Ivan Kelsall

From Tobin - _"Air doesn't really move in and out of the enclosure, either on a speaker or a mandolin"_. I own a pair of BBC Monitor quality l/speakers - Spendor SP1's. They are 'ported' as per the photo.,& if you hold a naked flame (a lit match) in front of the port,the flame will show that air is 'pulsing' through the port. The bass speaker's acting as a piston & in moving backwards,it displaces air inside the cabinet which in turn flows outwards through the port. Mine are the 11th pair of these speakers ever made,& i attended a demo.of them at a Hi-Fi show in London,where the designer, Spencer Hughes,demonstrated this very fact to all of us in the room. 
   In building L/speakers with 'ports',the designers could accurately control their frequency response. There's some info. here re. ''port or no port' designs for sub-woofers.The same principle applies to Hi-Fi speakers :- http://www.subwoofer-builder.com/vents.htm Notice the part in the ''port noise' paragraph re.''air _moving_ too quickly''. However,these fact may not hold true for _every_ ported design,my experience is only with my own,
                                                                                      Ivan :Wink:

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DavidKOS

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## Mandoplumb

My point about air moving in and out of speaker enclosures seems to have been misunderstood by some. As Ivan Kelsall describes the demonstration of his speaker he states that as the speaker cone moves backward it forces air out the port. If there was no port that air would restrict the movement of that cone, by the same way as the cone moves the other direction it creates a vacuum behind it that draws air in. Now I know that an instrument top doesn't move as much as a speaker cone but I still think the same principal is working. I know that that is very simple and other forces are present and there are more variables in instrument tops than speaker cones but that is one big reason for sound holes IMHO.

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## sunburst

> ...I know that an instrument top doesn't move as much as a speaker cone but I still think the same principal is working. I know that that is very simple and other forces are present and there are more variables in instrument tops than speaker cones but that is one big reason for sound holes IMHO.


It's all been observed, measured, and written down. We don't have to "think" we know how mandolins move air, we can read about it.
There are various modes of motion in mandolins, some result in movement of air in and out of the hole/s (sometimes referred to as an "air piston") and others do not. In other words, some of the mandolins methods of producing sound do not rely on nor result in air moving in the hole/s.
I keep having to say that I don't know much about speakers and that I'm only guessing (and yes, I know that it's all written down somewhere and I could look it up and read it, but I don't build speakers, so... also, since this isn't a speaker forum...), but I think that movement of the speaker cone pretty much always results in air movement in and out of the port because the box is made to be as inert as possible.

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DavidKOS, 

Timbofood

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## sblock

> From Tobin - _"Air doesn't really move in and out of the enclosure, either on a speaker or a mandolin"_. I own a pair of BBC Monitor quality l/speakers - Spendor SP1's. They are 'ported' as per the photo.,& if you hold a naked flame (a lit match) in front of the port,the flame will show that air is 'pulsing' through the port. The bass speaker's acting as a piston & in moving backwards,it displaces air inside the cabinet which in turn flows outwards through the port. Mine are the 11th pair of these speakers ever made,& i attended a demo.of them at a Hi-Fi show in London,where the designer, Spencer Hughes,demonstrated this very fact to all of us in the room. 
>    In building L/speakers with 'ports',the designers could accurately control their frequency response. There's some info. here re. ''port or no port' designs for sub-woofers.The same principle applies to Hi-Fi speakers :- http://www.subwoofer-builder.com/vents.htm Notice the part in the ''port noise' paragraph re.''air _moving_ too quickly''. However,these fact may not hold true for _every_ ported design,my experience is only with my own,
>                                                                                       Ivan


Ivan: Please read post #88.  This effect depends strongly on the frequency!  Significant amounts of air moving in an out of an enclosure only happen at low frequencies.  And they require a large input of energy.  Mandolins don't generate those frequencies.  Also, their plucked strings don't carry enough energy.  It is an innappropriate physical analogy to compare a mandolin with a (bass) speaker enclosure.  They operate in different regimes.  (Also, you don't need a port with a tweeter!)

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## T.D.Nydn

Sunburst,,the "air piston " thing,,what your saying ,sort of,is that some notes you play stay inside the mandolin,and some notes (to some degree) come out of the F holes? Is that why my mandolin sounds different when behind it than when in front of it?,,,

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## sunburst

No, that is not what I'm saying.
When we play a mandolin, or when we apply _any_ energy to the mandolin in the form of vibration, we excite all of the modes of motion in the mandolin. Some of those modes of motion cause air to "piston" in the port/s and some don't, but they are all in action whenever we play. No notes "stay inside the mandolin". Lower frequencies are mostly produced by motion of the air inside the mandolin, but the sound waves they produce, and that we hear, are obviously outside of the mandolin. Most higher frequencies are produced by the outside surface of the mandolin.

Don't expect a full explanation in a short forum post, there is too much information for that, and furthermore, I reach the limit of my ability to explain it if I get much further into it than this.

----------

T.D.Nydn

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## sblock

It is not physically accurate to think of a mandolin as a device that "pumps" air in and out through its sound hole (oval hole or ff holes). It is not an "air piston."  It is not like a ported (bass) loudspeaker. That is not really how it works.  A mandolin produces mainly treble frequencies.  These sounds radiate from a good many of its wooden parts, including large segments of the top and back. The underlying motions are quite small, measuring from mere fractions of a micron (that's one millionth of a meter) up to, at most, something on the order of 100 microns (at the bridge, where the amplitude if the string-induced motion is at its largest).

A mandolin, like all similar acoustic instruments, has a Helmholtz (air cavity) resonance, which is at the low frequency end of things.  This mode does involve the resonance of the air "trapped" inside the acoustic chamber, and not the vibration of the free surfaces. This resonance is definitely affected by things like the soundhole size (area) and the instrument's internal volume, and to a much lesser extent, soundhole shape and location.  It may be this resonance that folks have analogized as an "air piston", but that can be very misleading, and it has obviously led to some rather incorrect conclusions about how sound radiates from a mandolin, especially with regard to the putative effects on this sound that some have attributed to a pickguard/finger rest.  A finger rest does not "block the sound" from some kind of "air port" associated with a sound hole, people!  That's just wrong physics.

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DavidKOS

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## Emmett Marshall

> To that I say, hogwash.

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## sunburst

> It is not physically accurate to think of a mandolin as a device that "pumps" air in and out through its sound hole (oval hole or ff holes). It is not an "air piston."


There is at least one mode of motion where the top and back of a mandolin move up and down opposite of one another, the the air in the port/s (sound hole/s) does "piston" back and forth (in and out). It has been called a "bellows mode" (does not apply to bowl backs).
Dave Cohen said:



> ...a "piston" of air vibrating in the soundhole region. In practice, the amplitude of that motion is no more than about 3x to thickness of the top plate.


...so it is not a flow or air, so to speak, more or a "piston" vibrating up and down (in and out).

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## Mark Gunter

LOL, love the pic, Emmett!

sblock - I have read with interest the confused postings about how sound waves work. I did use the word "pump" and both John and Dave have used the word "piston" - these are not necessarily incorrect ways of speaking, but obviously have led to misunderstandings.

I make no claim to being an expert in acoustics, nor to have even half the knowledge about instruments that these luthiers have. My only purpose in posting my part of these exchanges was to point out (1) that sound does in fact issue from the sound hole, not merely from the air surrounding the plates, (2) that sheets of material between a listener and the source of sound will interfere with sound waves. I maintain that position. Further, neither you, John nor Dave have written anything to dissuade my belief. The type of effect any "baffle" might have on sound waves would be directional (reflective) and it is painlessly obvious that the effect could not be detected further than a meter or so from the instrument if at all.

This by no means refutes that in certain cases, the player, who is very near the instrument, might with his or her own hearing, detect some difference in sound with and without a pick guard, depending on how it is placed, theoretically.

There is really not much profit to be had in overly attempting to express these ideas here. There is good literature on acoustics, wave theory, musical instrument building, testing, etc. Folk who have trouble understanding how sound works should probably look elsewhere for more information.

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## Dale Ludewig

If you think Dave Cohen (in print) has written nothing to "dissuade" your belief, you do need to do some research.  And yes, there is a lot of good literature on acoustics and all such.

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## sblock

> LOL, love the pic, Emmett!
> 
> sblock - I have read with interest the confused postings about how sound waves work. I did use the word "pump" and both John and Dave have used the word "piston" - these are not necessarily incorrect ways of speaking, but obviously have led to misunderstandings.
> 
> I make no claim to being an expert in acoustics, nor to have even half the knowledge about instruments that these luthiers have. My only purpose in posting my part of these exchanges was to point out (1) that sound does in fact issue from the sound hole, not merely from the air surrounding the plates, (2) that sheets of material between a listener and the source of sound will interfere with sound waves. I maintain that position. Further, neither you, John nor Dave have written anything to dissuade my belief. The type of effect any "baffle" might have on sound waves would be directional (reflective) and it is painlessly obvious that the effect could not be detected further than a meter or so from the instrument if at all.
> 
> This by no means refutes that in certain cases, the player, who is very near the instrument, might with his or her own hearing, detect some difference in sound with and without a pick guard, depending on how it is placed, theoretically.
> 
> There is really not much profit to be had in overly attempting to express these ideas here. There is good literature on acoustics, wave theory, musical instrument building, testing, etc. Folk who have trouble understanding how sound works should probably look elsewhere for more information.


When excited by the vibrations of its strings, a mandolin vibrates in a multitude of complex ways, and these can be decomposed into "modes."  Some of the modes involve the movement of very tiny amounts of air in and out of the sound holes. Most of them do not, however.  And, as David Cohen has pointed out, the bulk movements of air do not extend much more then three times the thickness of the top beyond the instrument's surface.  Think about that fact for a moment:  it's not very far at all!  The movement doesn't reach as high as the fingerboard level on an F5, nor to the height of the pickguard.  To use the word "pump" in such a case is a bit misleading, unless you mean that any movement of air implies that it's somehow being "pumped," that is -- in which case, the word loses its traditional meaning. There is no NET movement of air, in any case, because the small movement (a few mm) is oscillatory, anyway.  Similarly, when you talk about "air pistons" and suchlike, you lose track of the fact that much of the vibratory energy (radiated sound) from a mandolin is not associated with any "piston-like" motions at all!  In fact, it's not all coming from the air cavity; it's associated with surface motion of the tonewoods.  It does not help to over-simplify the physics in such cases, especially when it leads so many musicians to reach the wrong conclusions, based on badly oversimplified notions of "pistons" and "pumps" moving air around. And clearly, folks HAVE reached the wrong conclusions.  Because that's not how it works.

I guess I have to disagree with you -- with all possible respect.  Yes, some of the mandolin sound DOES issue from the sound holes, as you wrote.  But the sound does not only, or even mainly, issue from the sound holes, as I and others have pointed out before. Furthermore, any sheets of solid material placed between a sound source and your ear will obviously affect the sound propagation, as you wrote.  But the degree to which this happens depends very much upon their location, size, acoustic impedance, and also the sound frequencies.  If you listen to a concert in an auditorium while holding a magazine at arm's length, it does little-to-nothing to change the sound field at your ears. But if you clap that same magazine tightly against one ear, it makes a huge difference! The location and size of a pickguard does little to affect the sound field of a mandolin, as discussed earlier in this thread. There are no real far-field differences, and only very minor near-field ones.  A pickguard does NOT muffle a mandolin.  And in this _diffractive_ limit, a small sheet -- be it a magazine or a pickguard -- does not act as a sound "reflector" (or baffle or mirror ) in quite the way that you're imagining. Once again, the sound does not travel in straight lines in the near field, and "reflect." Instead, it diffracts. You're not thinking about the physics properly (sorry).

As I mentioned in a previous post, the wavelength is the sound is large (or comparable with) the mandolin dimensions.  That means that near-in, the sound is diffracting, and not radiating away in straight lines (i.e., in spherical wavefronts).  ANYTHING, including your own playing hands (!!!!), as well as your head and body, can (and do) affect the sound pattern nearby.  In fact, the player is probably a much bigger perturbation to the near-field sound than any pickguard!  Most of this is completely inaudible in the far field, however, a few meters away.

I certainly have no quarrel with your argument that a player "who is very near the instrument, might with his or her own hearing, detect some difference in sound with and without a pick guard, depending on how it is placed, theoretically."  Yes indeed, this is perfectly possible. But so would small alterations in his or her playing position be expected to produce an audible difference.  And so would wearing different clothing, for that matter.

My bottom line is that a pickguard does not perturb the sound of a mandolin in any significant way. Certainly not in the far field, and only very modestly in the near field. It does not make it quieter from a few meters away. Does that mean that the change is totally inaudible/imperceptible to a nearby player, as opposed to someone in an audience?  Not at all.  Especially with the sensitive ears of the MC crowd!  But please, let's debunk the myth -- _and it IS a myth!_ --  that a pickguard somehow "muffles" or "baffles" the sound of a mandolin.  That's simply not true.  And even David Grisman, who thought that way in his early years, has come around 180 degrees on that point.

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## Mandoplumb

I don't understand why we say piston is wrong if the air is moving in and out as the top, back, or both flex that is pistoninng ( if there is such a word) if we are moving a ton of air or an amount so small it would be hard to measure. Noone thinks the mandolin is pumping like the port of sub woofers. Also Markscarts a baffle just affects the sound or air or whatever if it is between the source and you correct?  So to be practical there is no baffling effect for 99.9% of the listeners

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## Timbofood

I'm baffled!
I will leave the piston (pistoff) positive/negative speculation alone, I'd have a hard time not laughing myself silly.
This is so far beyond my pay grade I wouldn't know what to say.
I'm keeping my finger rest right where it is.

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## sunburst

> I don't understand why we say piston is wrong if the air is moving in and out as the top, back, or both flex...


It is a bit of a hold-over from describing an actual Helmholtz resonator. A mandolin functions as a modified Helmholtz resonator, but is not a true Helmholtz resonator, which is a spherical bottle, immobilized in sand, with a neck. The air in the bottle acts as a spring (compressing and decompressing) and the air in the neck of the bottle moves up and down the neck like a piston. A mandolin has no neck, in the same sense (bottle neck) so there is not the same air piston, but the air in the port/s does vibrate in and out to the extent that it does (a few millimeters), though the "pistoning" description is more accurate when describing a true Helmholtz resonator.

----------

sblock

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## Mark Gunter

By "pump" I mean no more than a "piston" of air, a volume of air (regardless of size or density) that moves in and out of the sound hole - it is ludicrous to think that I or any rational person would believe that some great volume of air is being pumped out of a sound hole. Please, do I sound that ignorant? (I'm laughing just thinking about the responses sure to follow that question :D )

Obviously, the volume of air moving in and out of the cavity is very small. By the same token, a person would have to be terribly slow not to comprehend that the movement of the top and back of a musical instrument will not cause a pulsation of air in and out of the sound hole.

Really, it seems as though many of you deliberately try to misunderstand and misinterpret what I've written. Perhaps it is because I am not writing in technical jargon, have only tried to make a point once or twice. Sorry to have gotten your hackles up, obviously my modes of expression are either too obtuse or just too simplistic and inaccurate for the scientists here. No harm, doesn't affect my main goal in being here, I'm learning new things daily. If it is that difficult to get my point across, either I am wrong or simply not eloquent nor technical enough, either way, I'm happy. On to the next big thing.

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## sblock

No one is accusing you of being ignorant! As I wrote, the facile use of words like "pump" and "piston" can be, and HAS BEEN, misleading, because it has led to some incomplete -- or even mistaken -- conclusions that follow from over-simplifying the physics, like these:

1) The sound from a mandolin comes out of its air holes. Not completely true! The sound is produced from many points on the mandolin surface. Only a fraction of the overall sound comes out the region near the air holes.

2) A pickguard acts as a sound "reflector."  Not true!  The pickguard is small compared to the sonic wavelength, and it mainly diffracts sound, rather than reflecting it.

3) A pickguard can "stifle" the vibrating air that emerges from the air holes.  Not true. The moving air only extends a few millimeters above the top of the sound hole, roughly three or four times the thickness of the top.  The pickguard is well above that point.

4) A pickguard limits the volume of a mandolin.  Completely false.  It does not perturb the sound in the far field.

and so on.  If you JUST limit your thinking to "pistons" that "pump air" you will be led to some very wrong conclusions.  Yes, these kinds of simple analogies can be helpful and have their place, but they break down when pushed too hard! And this is a case of just that.  A mandolin is not best approximated as a piston that pushes air in and out its soundhole. A lot more is going on, and if you neglect or ignore that in order to keeps things simple, you have the potential to get stuff wrong.

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## Mark Gunter

> No one is accusing you of being ignorant! As I wrote, the facile use of words like "pump" and "piston" can be, and HAS BEEN, misleading, because it has led to some incomplete -- or even mistaken -- conclusions that follow from over-simplifying the physics, like these:
> 
> 1) The sound from a mandolin comes out of its air holes. Not completely true! The sound is produced from many points on the mandolin surface. Only a fraction of the overall sound comes out the region near the air holes.
> 
> 2) A pickguard acts as a sound "reflector."  Not true!  The pickguard is small compared to the sonic wavelength, and it mainly diffracts sound, rather than reflecting it.
> 
> 3) A pickguard can "stifle" the vibrating air that emerges from the air holes.  Not true. The moving air only extends a few millimeters above the top of the sound hole, roughly three or four times the thickness of the top.  The pickguard is well above that point.
> 
> 4) A pickguard limits the volume of a mandolin.  Completely false.  It does not perturb the sound in the far field.
> ...


To your specific points:
1) Sound does issue out of the sound hole; it has been stated by others in this thread that sound does not issue from the sound holes. I would challenge you to find where I have written that all the sound comes out of sound holes, or even the majority of it. I'm basically in agreement with what you've written in point #1, but I don't remember anyone writing in this thread that all sound comes from the sound holes. I do remember someone writing that sound does not issue from the sound holes, and only from the vibrating top plate.

2) I do not wholly agree with your point #2, because it is not obvious to me. I can imagine that a flat piece of material like a pickguard, depending upon the properties of material from which it is made, might have a directional effect due to reflection (bouncing) of audio waves, albeit not enough of one to affect the sound from any great distance.

3) This is a common belief, but I agree an incorrect one, and "stifle" is not an appropriate term in my mind for any effect, great or small, that a pickguard may have. A pickguard probably won't alter the acoustics to any great extent. It may be possible for the player to note a difference nonetheless.

4) I agree with number 4.

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## Mark Gunter

I suppose I originally got a little incredulous about Dave calling "baloney" on a person who had posted, and I might even agree with him, having gone back to see what specifically he was responding to (post #36). Earlier, a person had stated that he could hear a difference on his personal instrument when the pick guard was removed (post #20). I see no reason to question his personal experience even after all this. I find Dave Cohen's second message here to be very instructive, and thank him for the input. He's probably forgotten more about these things than I could ever hope to learn. If I've given the impression that I am in the camp that believes pick guards are evil, then I've given the wrong impression. I'm merely of the opinion that if a player believes he can hear a difference in his own mandolin with and without a pick guard, I have no reason, scientific or otherwise, even after reading all this, to believe otherwise.

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## MDMachiavelli

I have the Fender FM100 and it has a pick guard, but I never noticed that a lot of them don't.

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## Ivan Kelsall

From sblock - _" Significant amounts of air moving in an out of an enclosure only happen at low frequencies."_. I did mention that the air was forced out by the movement of the_ bass cone_ or words to that effect !. My answer was in response to the assertion that air doesn't move in & out of a _loudspeaker_ port - i never made any comment re. mandolins. I don't know enough about those to make any useful comment. That expertise lies squarely with folk as knowlegeable as David Cohen,
                                                                                                                                                       Ivan :Wink:

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## Dave Cohen

There are a couple of things that need to be clarified here.  First, the oscillatory motion of air in the soundhole(s) _does_ lead to sound radiation at lower frequencies.  That is true for guitars, mandolins,..., and bowed string instruments as well.  The oscillatory motion of air in the soundhole(s) acts on the air adjacent to it, leading to propagation of sound waves outward from the instrument.  Further, soundhole radiation resulting from the coupling of the first (i.e., (0,0) or T(1,1) doublet) modes with the Helmholtz resonance is the main event in plucked string instruments up to what is sometimes called a "critical frequency".  A similar event occurs in bowed instruments, even though there is no true T(1,1) mode.  I alluded to that without saying it directly in an earlier post.  The critical frequency is the frequency at which the velocity of the plate motion becomes equal to the sound speed in the adjacent air.  Below the critical frequency, there is not much sound radiation coming off the plate surface.  Above it, there is significant sound radiation from the plate.  Iirc, the critical frequency for air at ambient conditions is around 1.5 kHz or above.  The soundhole radiation in the 200-450 Hz range (i.e., from the ""main event") is monopole radiation.  In ff-hole type mandolins, the radiation above that range is dipole radiation - not as strong  There may be some more monopole radiation in oval hole mandolins up around 700-800 Hz, but in my observations, it was not very strong.

Second, plucked string instruments, much more than bowed string instruments, are mainly low-frequency animals.  In bowed string instruments, the bow is supplying energy to the strings, and in turn to the body, repeatedly via the so-called "Helmholtz motion", a sawtooth pattern of force vs time.  The bow repeatedly pulls the string and lets it slip, supplying force with each slip.  In plucked string instruments, all you have is the single pluck.  Consequently, there is much more output in bowed string instruments above 1.5 kHz, and even a "formant" up around 2-2.5 kHz.  With plucked strings, you just get a lower and diminishing amplitude "resonance continuum" above 1.5 kHz.

I'm not sure what was meant by "high frequency" in mandolins, but the "main event" occurs in oval hole mandolins around 200-450 Hz, and in ff-hole type mandolins, around 250-450 Hz.  Because the plucked strings are supplying less energy in the region above 1.5 kHz, there is no formant, i.e., much less high-frequency output than with bowed strings.

The sound radiation from plates is not only in the literature, but is covered in textbooks as well.  F'rinstance, it is covered in the Fletcher & Rossing text, section 7.8, pp 186-189.

----------

CedarSlayer, 

DavidKOS, 

Emmett Marshall, 

hank, 

Mark Gunter

----------


## Dave Cohen

Forgot to add that things like Neapolitans (aka "bowlbacks"), domras, balalaikas, & lutes are a bit different, owing to having a very stiff bowl instead of a back plate, relatively stiff ladder-braced top plates, and often a very low Helmholtz resonance frequency.  They are somewhat decoupled because of a frequency separation between the main top plate mode and the Helmholtz resonance.  But even with those things, there is _some_ coupling and soundhole radiation.  I touched on that in my chapter in the Rossing book, "The Science of String Instruments" (Springer, 2010).

----------

DavidKOS, 

Emmett Marshall, 

hank

----------


## Emmett Marshall

I can always count on the Mandolin Cafe for my weekly fix of theoretical physics! :Grin:

----------

Drew Egerton, 

Mark Gunter, 

Mark Wilson

----------


## Timbofood

I think my brain just sprung a leak! 
All this science for finger rests, and pick guards. Boggles the mind!
I need more coffee!

----------


## Emmett Marshall

> I think my brain just sprung a leak!


Actually, because of this thread, I am compelled to experiment. I think I might be on to something really big here.  I plan to run a garden hose from my "F hole" to my right ear canal.  If it works, as I suspect it will, I won't need to spend $500 on a set of stage monitors this month.

----------

Mark Gunter

----------


## Dave Cohen

All this science just for pickguards?  Well, I didn't bring it up, I just responded to it.  As for "theoretical", most of it is actually experimental.

The antipathy to science is a constant source of dismay to those of us in the science education biz.  Neil Tyson said it well in an interview on the Charlie Rose program.  He said something like "look,with regard to the all too common expression by so many people that they are not good at science and math, so they just stick to humanities and social sciences and such, If I were to say something like 'I'm not good at those nouns and verbs, so I just stick to my physics and equations', _you (and everyone) would just laugh at me_".  Couldn't have said it better myself.  In fact, I've not found the words before his statement to say it anywhere near as well as he did.

----------

Emmett Marshall, 

hank, 

sblock

----------


## Emmett Marshall

Hey Dave, Actually your explanations are very helpful and informative.  I don't have an antipathy toward science. I spend hours each week reading science news, etc. It's just that struggling through college algebra taught me two valuable lessons:  1) I'm not smart. 2) Ignorance is bliss.  You _are_ appreciated!

----------

Rick Jones, 

Timbofood

----------


## Bertram Henze

> Actually, because of this thread, I am compelled to experiment. I think I might be on to something really big here.  I plan to run a garden hose from my "F hole" to my right ear canal.  If it works, as I suspect it will, I won't need to spend $500 on a set of stage monitors this month.


I works.  :Cool:

----------


## Emmett Marshall

Dang.  Somebody beat me to it!

----------


## Timbofood

See, all those inventions, gizmos, and attachments we keep coming up with were invented by Rube Goldburg (Goldberg?) already! I'm working a rather involved piece of nothing which will probably end up taking hours of valuable napping resources. I will post pictures if it does anything near what it is supposed to.
It's not the science that causes my head to swell, it's the explanation of the science. 
 :Wink: 
You do really explain the nature of the acoustical issues quite clearly, Dave.

----------


## Mark Gunter

The textbook Dave Cohen referred to, _The Science of Stringed Instruments_, is freely available online in PDF format for anyone interested: http://logosfoundation.org/kursus/Th...nstruments.pdf

----------


## sblock

But science is nothing more or less than a series of explanations. (Good explanations, and testable ones, but explanations nonetheless).

----------


## Loudloar

I posted on page one of this thread, three years ago!!



> I can tell you that on my 1924 F-5 there's no doubt that it dampens the E and A strings. I'm convinced that it's due to the weight attached to the end of the fingerboard rather than any blockage of the treble f-hole.


I'm in total agreement with the folks who say the finger rest doesn't block sound coming from the f-hole. In my opinion the finger rest is too far from the surface of the top to interfere with the sound waves from the f-hole.
BUT it's provable that the finger rest mutes the E and A strings (at least on my instrument.) As you probably know a Gibson finger rest is attached with two pins into the side of the fingerboard and a bracket screwed to the side of the mandolin. I can leave the bracket unattached but the finger rest held on by the pins only, play the instrument; then slip the finger rest off and play the instrument again. (And repeat as often as desired.) These two examples of playing are only a few seconds apart so it makes it possible to compare the sound accurately. With the finger rest attached there is a small but clearly discernible muting of the high strings. I can't detect any change in the overall loudness of the instrument. I would imagine I could attach an equivalent weight to the edge of the fingerboard and get the same effect. It's not a huge difference but it is undeniable. I won't claim that every mandolin on the planet would behave the same way, as construction and responsiveness can vary between instruments.

Steve

----------


## Jim Adwell

> I posted on page one of this thread, three years ago!!
> 
> I'm in total agreement with the folks who say the finger rest doesn't block sound coming from the f-hole. In my opinion the finger rest is too far from the surface of the top to interfere with the sound waves from the f-hole.
> BUT it's provable that the finger rest mutes the E and A strings (at least on my instrument.) As you probably know a Gibson finger rest is attached with two pins into the side of the fingerboard and a bracket screwed to the side of the mandolin. I can leave the bracket unattached but the finger rest held on by the pins only, play the instrument; then slip the finger rest off and play the instrument again. (And repeat as often as desired.) These two examples of playing are only a few seconds apart so it makes it possible to compare the sound accurately. With the finger rest attached there is a small but clearly discernible muting of the high strings. I can't detect any change in the overall loudness of the instrument. I would imagine I could attach an equivalent weight to the edge of the fingerboard and get the same effect. It's not a huge difference but it is undeniable. I won't claim that every mandolin on the planet would behave the same way, as construction and responsiveness can vary between instruments.
> 
> Steve


You've failed to determine whether the effect you hear is caused by 1) the finger rest *** being attached to the fingerboard, or 2) the finger rest being in place whether connected to the fingerboard or not.  You need another experiment where you attach the finger rest by the bracket only without the fingerborad touching it at all.




> I would imagine I could attach an equivalent weight to the edge of the fingerboard and get the same effect.


Imagination is all well and good, and even indispensable for scientific investigation, but experiment is more important, especially one like this which is doable and can potentially disprove your contention.  Attach the weight and see what happens.


*** Sheesh, now I'm calling a 'finger rest'.  It's a pickguard, dammit.  :Smile:

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## sblock

Why don't you post some recordings of your mandolin being played with and without its finger-rest/pickguard, but not tell folks which is which, and see if people on this forum can hear the difference?  Of course, this is not a fully controlled experiment, since you know which condition is which, and can thereby change the way that you play (either consciously or unconsciously), but it's a start, and would give folks an idea of the size of the effect.  We could use some data for this discussion!

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## Bertram Henze

> I think my brain just sprung a leak!


Come on, we have not even considered Schrödinger's cat being inside the mandolin body (dead or alive) yet.

----------

Timbofood, 

xSinner13x

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## Mandoplumb

Now we need to do 6 pages to determine if a little added weight attached to the fingerboard will mute the first and second strings. Just to get the ball rolling I don't see how, although

----------


## Dave Cohen

> Come on, we have not even considered Schrödinger's cat being inside the mandolin body (dead or alive) yet.


Right, and of course the cat has a dead state AND an alive state.

----------

Timbofood

----------


## MikeEdgerton

If it's dead or alive is it still Schrödinger's cat?

----------

DavidKOS, 

Jill McAuley

----------


## Timbofood

You guys!

----------


## Bernie Daniel

> I posted on page one of this thread, three years ago!!
> 
> I'm in total agreement with the folks who say the finger rest doesn't block sound coming from the f-hole. In my opinion the finger rest is too far from the surface of the top to interfere with the sound waves from the f-hole.
> BUT it's provable that the finger rest mutes the E and A strings (at least on my instrument.) As you probably know a Gibson finger rest is attached with two pins into the side of the fingerboard and a bracket screwed to the side of the mandolin. I can leave the bracket unattached but the finger rest held on by the pins only, play the instrument; then slip the finger rest off and play the instrument again. (And repeat as often as desired.) These two examples of playing are only a few seconds apart so it makes it possible to compare the sound accurately. With the finger rest attached there is a small but clearly discernible muting of the high strings. I can't detect any change in the overall loudness of the instrument. I would imagine I could attach an equivalent weight to the edge of the fingerboard and get the same effect. It's not a huge difference but it is undeniable. I won't claim that every mandolin on the planet would behave the same way, as construction and responsiveness can vary between instruments.
> 
> Steve


H.  Not to be a pain in the rear but if your proof is based on what you *think* that you hear that is not proof. 

Rather that is your opinion--however strongly held.  

Now if your ears happened to have an electronic device embedded for measuring sound waves and you recorded the difference in volume, pitch or shape quantitatively THEN you would have proof.   :Smile:

----------


## Dave Cohen

> H.  Not to be a pain in the rear but if your proof is based on what you *think* that you hear that is not proof. 
> 
> Rather that is your opinion--however strongly held.  
> 
> Now if your ears happened to have an electronic device embedded for measuring sound waves and you recorded the difference in volume, pitch or shape quantitatively THEN you would have proof.


Nope, not even THEN.  You know the doctrine of falsifiability.  We don't prove.  What he would have would be, e.g., corroboration, or demonstration, or verification, or,......, but NOT proof.

----------


## Mandoplumb

What I hear is proof for me. Science proves something today then something different tomorrow so I can do the same thing. Prove the cat is dead today and maybe it's alive tomorrow. All kidding aside how do we really prove the things we have been talking about, a lot of knowledgeable people have stated slightly different proofs. Probably all are correct as for as it goes, but come on we are talking art, how do you prove art.

----------


## sblock

If I may, David Cohen seemed to be making a point that's related to the philosophy of science, and one made famous by the late Karl Popper, among others.  The basic idea is to recognize that the universe of all possibilities is truly VAST, and therefore it is (usually) a practical impossibility to prove that something is "true" _to the exclusion of all other possibilities_, if for no other reason than that there are simply too many of those possibilities to be tested.  On the other hand, it is often possible (usually) to falsify an idea, by simply showing that the idea is inconsistent with observations.  In simpler (but slightly less accurate!) terms, you can show that something is wrong, but it's very hard to show that something is right (to the exclusion of any other explanation). In other words, ideas are FALSIFIABLE.  They are not really "provable." 

It is not possible to "prove" that a pickguard does not affect the sound quality of a mandolin. Whatever that means.  On the other hand, it is certainly possible to test whether someone can -- or cannot -- reliably distinguish the sound of their own mandolin with or without its pickguard, when it's being played by someone else in a blind test.  That is, can someone reliably detect the presence or absence of the pickguard simply by listening to the mandolin's sound, without other clues?  If they cannot tell, then we have falsified the notion that the pickguard affects the tone.  For them, that is! It's always possible that someone out there exists with super-ears who can tell, and at better than chance levels.

Scientists try to be very careful about claims, and they seldom use the word "prove," because it's so loaded.  But they are skeptical, and they tend to use "disprove" a lot more!  The best we can do with the claim that a pickguard changes the sound of a mandolin is to TEST that claim in a valid, controlled way.  As many of you realize, "seeing is believing" is a rather flawed concept.  "Hearing is believing" is probably just as flawed.

Any yes, I am extremely skeptical of the claim that someone can hear a change in tone when his pickguard is attached.  Especially when no attempt was made to control for observer bias. This does not invalidate their _experience_.  They might believe perfectly well that the sound changed.  But they also _saw_ whether the guard was on or off!  Plus, we all have preconceived notions, whether we admit to these or not. They may accept their own anecdotal evidence developed in this way ("I believe my own ears!").  But I don't.

----------

Emmett Marshall, 

StuartE

----------


## Dave Cohen

Mathematicians can prove.  So can philosophers and logicians.  Lawyers _claim_ to offer proof.  All because they can show by logical extension that if something is true for one case now, it will be true for any particular case in the future.  In science, experiment always has the last word.  Even though we may have some intuitive idea of the outcome of an experiment, in principle, we are doing the experiment because we do not know the outcome with certainty.  There is always the possibility that a future experiment will contradict or even negate our present results.  Ergo, we cannot prove in science.  We can demonstrate, corroborate, verify,..., but not prove.

----------


## Mark Gunter

> Now if your ears happened to have an electronic device embedded for measuring sound waves and you recorded the difference in volume, pitch or shape quantitatively THEN you would have proof.


LOL, the electronic gadgets are there to teach you something about what it is you're hearing or not hearing, to suggest that the electronic gadget can prove that you heard something? OK, I'll leave that one alone. It's like, "Make a recording, and transfer to us via electronic impulses carrying digital data through a series of servers so that we may verify through blind testing what it is you are hearing (or not) with your eardrums in your own room."

OK, y'all just go for it, fellows.  :Wink:

----------

Petrus

----------


## Mark Gunter

Good to see that the discussion has turned a bit toward philosophy. A couple of observations:

1. None of us will probably ever know what loudloar heard, or is hearing, in this case or why he hears what he testifies to hearing. An electronic gadget and a series of blind tests won't help. And unless you happen to be omniscient, omnipresent and infallible then there's no point in adamantly denying what another person experiences. You can doubt away, and happily; you can even try to persuade him that he's mistaken, and perhaps you will prevail.

2. Never underestimate the placebo effect. At the beginning of this discussion I might have sworn that I in my near deaf state could never tell the difference in sound between pick guard on/off at any distance. But now, miraculously, I can hear the difference! In fact, the sound coming from the lower f-hole has gotten louder and I can easily make a distinction between the resonance of the f-hole nearer me and the lower one! The resonance from the lower one is stronger! At times, I can almost see the sound waves coming from it.

I've read the article referenced earlier, as well as chapter 6 in the text book - also, I very much doubt that any listener could truly hear the difference on a mandolin with/without pick guard from a short distance away. In short, I am in agreement with most parties here on that particular issue in general. But in my living room, I could sense audibly, in a manner so real as to practically visualize the sound!

Do not underestimate the placebo effect, or the variety of human experience.

----------


## Dave Cohen

Mr. Carts, the point of recording quantitative measurement is that (a) you can repeat it and thereby judge it's reliability, (b) it becomes a point of comparison for other and future observations, and (c) most important, [someone else[/I] can repeat it under the same conditions and hopefully get the same result(s).  Without those three markers, your eardrums are producing only anecdotes.  Further, audial memory is good for maybe 0.4 seconds, no more than 10x that under best conditions.  You record it quantitatively, and you have preserved it for comparison and evaluation.  You can be as dismissive as you like, but anecdotes neither advance knowledge nor settle arguments.

----------

hank, 

Jim Adwell, 

Timbofood

----------


## Mark Gunter

Mr. Cohen, I meant no disrespect by my lighthearted remarks. It's Mark Gunter, markscarts is simply a username I frequently use. I do understand the value in your work, and I feel we are privileged to have your input. I am enjoying the fruits of your studies, and understanding a bit of it. I was being a bit "funny" in my mode of expression, but I was writing the truth for the most part, as I see it. And, in no way intending to be dismissive of your work, or of your methods. I assume it would not be your method to implant devices in a person's ears in the manner someone else has suggested? And I hope you see my point about making a recording on just any old device, sending it over here in order to blind test the recorded sounds in hope of understanding what loudloar is experiencing? My reference to your work was given only to indicate that I had read it, I think it is great. I was being specifically dismissive of the other suggestions made here. Sorry for the confusion.

----------


## Rick Jones

> I reach the limit of my ability to explain it if I get much further into it than this.


This may be the best phrase I have ever read, anywhere, on any topic, and pretty much defines my life! I may steal this one for future use/abuse.  :Grin: 

John - in all seriousness, a huge thank you for all your contributions to the forum. They are always appreciated, probably much more than you know.

----------


## xSinner13x

Well my 2 cents:
If you play with a destructive technique and don't use a guard,
you have NO ONE to blame but yourself.

I have left the *Scratch Guard* on my vintage mando, just for that reason, 
To prevent Scratches, be it from picks or fingers(trim your damn nails ya buncha ladies)...  :Laughing: 
(as to the issue of "Borrowing", I see it kinda like swapping significant others, NO I don't wanna crack at yours...)
I also use it as a rest, as I tend to plant my pinkie on it *Not The Body*

As to tone, a subjective issue no matter the instrument, As I like to taunt the folks in the guitar forums...
*Tone Is In The HANDS*
(this should really burn some nerd boy butt...)

----------


## Dave Cohen

> Mr. Cohen, I meant no disrespect by my lighthearted remarks. It's Mark Gunter, markscarts is simply a username I frequently use. I do understand the value in your work, and I feel we are privileged to have your input. I am enjoying the fruits of your studies, and understanding a bit of it. I was being a bit "funny" in my mode of expression, but I was writing the truth for the most part, as I see it. And, in no way intending to be dismissive of your work, or of your methods. I assume it would not be your method to implant devices in a person's ears in the manner someone else has suggested? And I hope you see my point about making a recording on just any old device, sending it over here in order to blind test the recorded sounds in hope of understanding what loudloar is experiencing? My reference to your work was given only to indicate that I had read it, I think it is great. I was being specifically dismissive of the other suggestions made here. Sorry for the confusion.


I didn't think you were at all dismissive of me or my work, but I thought the tone was somewhat dismissive of science.  And since I identify so strongly with science, dismissiveness toward science is one of the things that pushes my buttons.

----------


## Bernie Daniel

> Nope, not even THEN.  You know the doctrine of falsifiability.  We don't prove.  What he would have would be, e.g., corroboration, or demonstration, or verification, or,......, but NOT proof.


Dave is correct of course as regards a strict use of the concept of proof (or to prove).  

I think part of the problem is how "universal" or general are you claiming for your evidence is "proof" of some phenomenon.  

For example, instrumented tests on one mandolin performed with and then without a pick guard could establish that you can show that the pick guard is changing the measured properties of the sound coming from the instrument.  Some might say that "proves" it is happening at least for that particular instrument.  

But of course it in no way does that one test establish that the same result would happen with the next mandolin that you tried the same test on.

If you did the test on 100 mandolins and got the same results than you would have established a greater likelihood that that pick guards do impact the tonal output of a mandolin and if you tested a 1000 mandolins then you have even a greater likelihood.  

But you have not* proven* it in the absolute sense because on the 1001st mandolin tested you might fail to measure any influence of the guard! 

But unfortunately common use of words tends to "pollute" then (IMO).  The term "entropy" is a specific concept in thermodynamics describing the uncertainty or disorder in a system as a function of temperature or heat with very specific and predictable consequences for the system but as the word has crept out into common language you often see it used in inexplicable way.

Merriam-Webster on proof:

1. a.  the cogency of evidence that compels acceptance by the mind of a truth or a fact
b.  the process or an instance of establishing the validity of a statement especially by derivation from other statements in accordance with principles of reasoning;

2. obsolete :  experience;

3.  something that induces certainty or establishes validity;

4. archaic:  the quality or state of having been tested or tried; especially :  unyielding hardness;

5.  evidence operating to determine the finding or judgment of a tribunal;

6.  plural: proofs or proof :  
a. copy (as of typeset text) made for examination or correction;
b. a test impression of an engraving, etching, or lithograph;
c. a coin that is struck from a highly polished die on a polished planchet, is not intended for circulation, and sometimes differs in metallic content from coins of identical design struck for circulation;
d. a test photographic print made from a negative;

7. a test applied to articles or substances to determine whether they are of standard or satisfactory quality;

8. a the minimum alcoholic strength of proof spirit
b   strength with reference to the standard for proof spirit; specifically :  alcoholic strength indicated by a number that is twice the percent by volume of alcohol present <whiskey of 90 proof is 45 percent alcohol.

Anyway.............

----------

Mark Gunter

----------


## Givson

I have a Duff F-5 mandolin with a mini pickguard, attached to the fingerboard extension with three pins, and no clamp or bracket attached to the body of the mandolin.   I have been a musician for many years, and my "ears" are very good.  I have tested with pickguard on and off repeatedly, and my experience is close to loudloar's.  I find that the high frequencies appear to be diminished with the pickguard on, in addition to reduced sustain of the harmonics on the E and A strings.  There appears to be less "air" in the highs with the pickguard on.  
I have not attempted to determine whether the sonic difference is caused by the additional weight of the pickguard attached to the fingerboard extension, or if the plastic pickguard somehow filters the sound emitted by the TOP of the mandolin.  For whatever reason(s), the tonal response is altered with the pickguard on, with a reduction in the high end.   
The decision to use a pickguard or not is a personal choice.  Ultimately, musicians need to trust their ears.

----------


## Bertram Henze

> If you play with a destructive technique and don't use a guard,
> you have NO ONE to blame but yourself.


That brings back the original practical purpose of the pickguard. If it is needed, it is needed. If it is not needed, why optically obliterate half a beautiful instrument?

----------

Bernie Daniel, 

DavidKOS, 

Jess L.

----------


## DavidKOS

> That brings back the original practical purpose of the pickguard. If it is needed, it is needed. If it is not needed, why optically obliterate half a beautiful instrument?


Because it is needed for some playing styles and in the way for others. That's what I have gathered from the player's responses on this and other threads. 

No judgement intended:

If you play more with classical pick technique (thin stiff sharp pick, subtle dynamics and articulations, etc.) the pickguard is very useful.

If you are hitting the mandolin hard Bluegrass-style with a large thick often rounded pick and trying to be loud enough to be heard over the banjo, then a pickguard could be in the way.

Thus there is no single rule.

----------

Timbofood

----------


## sunburst

> ...For example, instrumented tests on one mandolin performed with and then without a pick guard could establish that you can show that the pick guard is changing the measured properties of the sound coming from the instrument.  Some might say that "proves" it is happening at least for that particular instrument...


If we were to apply the scientific method to the question of whether or not a pick guard/finger rest affects the sound of a mandolin, I think we would be best served by a double blind listening test with a large sample size of players, listeners and instruments. If it can be shown that listeners and/or players can distinguish the sound of mandolins with and without pick guards at a rate significantly better than chance, we have presented evidence that there is a difference in the sound of a mandolin with and without a pick guard. If the results are no better than expected from chance, we've presented evidence that there is no difference in sound. Let several more groups try the same experiment and show similar results, and we accumulate more evidence that there is or is not a difference in sound, but we can repeat the experiment as many times as we can and we can never _prove_ that there is or is not a difference.

I know this has been brought up many times and that some people are darned tired of it, but reading these articles "changed my life" so to speak. I know from experience that there are people who hear things that I do not hear, that we can learn to hear (and see) things that we have previously missed, so I've never entirely dismissed someone's claim to hears something that I do not. That has led me to accept the claims of many people who say they hear distinctions that I do not hear.
Then along came these studies, both well designed and carried out, the second in particular, that lead to these results:
http://josephcurtinstudios.com/artic...is-experiment/
http://www.thestrad.com/cpt-latests/...n-instruments/

Of all the claims by people to hear something, to be absolutely sure of it, to believe it to the depths of their beings, we would be hard pressed to find any more strongly held beliefs than those of many high level violinists, that antique violins are superior in many ways, especially in sound, to modern violins. Those were the people participating in these tests!
What did I learn from reading these articles?
-That sometimes (often?) claims to hear something that I do not hear may be unfounded.
-That antique violins, despite their centuries-old reputations, perhaps do not sound significantly better than modern instruments.
-That people, when their beliefs are called into question by scientific evidence, will often dismiss the scientific results as invalid: The test wasn't well designed, the testers were biased, etc.. People with strongly held beliefs can be very reluctant to accept the possibility that they may be wrong.
-That things that I am sure of could be shown to perhaps be wrong by a well designed double blind (or other scientific) test. The high level violin soloists in the studies are well educated, professional musicians who have basically eaten, slept and breathed violins and music from a very early age (no one else becomes a top level soloist), yet they are human beings, just like me. Why would I expect to fare any better in a double blind test than they did? Yet there are those who will say, "yeah, but..." and continue to claim that they can hear what may or may not actually be there. It's an attitude that I don't completely understand. It seems to me that if we consider ourselves to be humans on an equal footing with other humans, we must assume that we are subject to the same prejudices, conditioning and self deception, and that we are equally likely to find out that evidence indicates we may be wrong.

So anyway, there is a little background in why I have recently become more skeptical of people's claims to be able to hear and distinguish sounds on very subtle levels, and yet I remain aware that "perception is reality" and that if someone _thinks_ he/she hears something, that's as good as actually hearing it for that individual. That individual who hears what others do not, in my opinion, should not insist that what he/she hears is real and that the rest of us just don't hear it, unless there is some sort of evidence (not anecdotal!) to back up that claim.

----------

Bernie Daniel, 

DavidKOS, 

Jim Adwell, 

sblock

----------


## DavidKOS

> If we were to apply the scientific method to the question of whether or not a pick guard/finger rest affects the sound of a mandolin, I think we would be best served by a double blind listening test ......
> 
> ......
> Of all the claims by people to hear something, to be absolutely sure of it, to believe it to the depths of their beings, we would be hard pressed to find any more strongly held beliefs than those of many high level violinists, that antique violins are superior in many ways, especially in sound, to modern violins. Those were the people participating in these tests!
> What did I learn from reading these articles?
> -That sometimes (often?) claims to hear something that I do not hear may be unfounded.
> -That antique violins, despite their centuries-old reputations, perhaps do not sound significantly better than modern instruments.
> -That people, when their beliefs are called into question by scientific evidence, will often dismiss the scientific results as invalid: The test wasn't well designed, the testers were biased, etc.. People with strongly held beliefs can be very reluctant to accept the possibility that they may be wrong.
> -That things that I am sure of could be shown to perhaps be wrong by a well designed double blind (or other scientific) test. 
> ...


In so many areas of musical mythology, the commonly held wisdom has never been properly tested. All of the anecdotal evidence does not mean anything compared to real double-blind tests.

However there seem to be very few such studies,  leaving most of us to debate these issues based on opinion rather than facts.

One of my favorites is the "tube amps sound better than SS guitar amps" myth.  I recall a few studies where listeners could not tell accurately which type of amp was being used - even though so many guys claim they can tell.

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Bernie Daniel

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## Jim Adwell

> One of my favorites is the "tube amps sound better than SS guitar amps" myth.  I recall a few studies where listeners could not tell accurately which type of amp was being used - even though so many guys claim they can tell.


That's from the old "crossover noise/distortion in transistor amps" thing from ~50 years ago.  The earlier solid state amps were easy to distinguish from the tube amps of the day by the high frequency distortion present (assuming one's hearing was sufficiently acute in the higher frequencies).  Newer types of devices and different circuit designs fixed that long ago, but the idea keeps getting resurrected from time to time, probably by makers of retro tube amps.  :Wink:

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DavidKOS, 

Jess L., 

MikeEdgerton

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## Rick Lindstrom

> (EDIT) It's an attitude that I don't completely understand. It seems to me that if we consider ourselves to be humans on an equal footing with other humans, we must assume that we are subject to the same prejudices, conditioning and self deception, and that we are equally likely to find out that evidence indicates we may be wrong.(EDIT)


Most people are pretty reluctant to question the validity of their dearly held assumptions, or guiding fictions (as Albert Adler would have called it). In fact I don't think it ever occurs to people to do so. They just "know what they know". Present group excepted,of course. 

 :Smile:

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Bernie Daniel, 

DavidKOS, 

Jess L., 

sblock

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## Wes Brandt

> .One of my favorites is the "tube amps sound better than SS guitar amps" myth.  I recall a few studies where listeners could not tell accurately which type of amp was being used - even though so many guys claim they can tell.


Better? they certainly can sound very different and unless you only use very "clean" sounds, there are many things that a tube amp can do that a transistor amp cannot, ...unless it has tube amp modeling built into it like so many modern ones do

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## sblock

> Better?… they certainly can sound very different and unless you only use very "clean" sounds, there are many things that a tube amp can do that a transistor amp cannot, ...unless it has tube amp modeling built into it like so many modern ones do…


Yes, but I think that's precisely the point!  There is nothing intrinsically "superior" about the sound of tube amps -- it's just that many folks prefer the sounds of their 'softer' nonlinearities when they're overdriven (and it's also what they were used to).  But with suitable circuitry, modern transistor-based amps can be constructed that are sonically indistinguishable from tube amps, because they have the same gain and same non-linearities.  And with today's digital synthesis capabilities, it's possible to model just about any arbitrary audio response (transfer function) in an audio amp.   Each year, there are fewer and fewer "experts" around who claim they can still hear the difference.  

As the great physicist Max Planck pointed out, "Science advances, one funeral at a time."

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Bernie Daniel, 

Jess L.

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## DavidKOS

> Better? they certainly can sound very different and unless you only use very "clean" sounds, there are many things that a tube amp can do that a transistor amp cannot, ...unless it has tube amp *modeling* built into it like so many modern ones do


Which are my current amps of choice, digital modeling amps.




> Yes, but I think that's precisely the point!  There is nothing intrinsically "superior" about the sound of tube amps -- it's just that many folks prefer the sounds of their 'softer' nonlinearities when they're overdriven (and it's also what they were used to).  But with suitable circuitry, modern transistor-based amps can be constructed that are sonically indistinguishable from tube amps, because they have the same gain and same non-linearities.  And with today's digital synthesis capabilities, it's possible to model just about any arbitrary audio response (transfer function) in an audio amp.   *Each year, there are fewer and fewer "experts" around who claim they can still hear the difference. * 
> 
> "


That is the whole point. Some technology is outdated, some people still like to use it, it all depends on the musical need. It's not always a simple case of "better".

Tube or SS....pickguard or none....and so on.

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sblock

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## Timbofood

It's rather like when my brother died,
My wife told me: "It doesn't get better, just different"
That might be a little off the topic but, when things change humans adapt, it's just what we do, we resist but eventually we must change, change is the only constant.

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## xSinner13x

> That's from the old "crossover noise/distortion in transistor amps" thing from ~50 years ago.  The earlier solid state amps were easy to distinguish from the tube amps of the day by the high frequency distortion present (assuming one's hearing was sufficiently acute in the higher frequencies).  Newer types of devices and different circuit designs fixed that long ago, but the idea keeps getting resurrected from time to time, probably by makers of retro tube amps.


Yeah just go look at the new Roland Blues cube online.
EJ is dyed in the wool Plexi man....




Sorry for steering things OT, BACK TO PICK GUARDS.....

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Dobe

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## Wes Brandt

> Yes, but I think that's precisely the point!  There is nothing intrinsically "superior" about the sound of tube amps -- it's just that many folks prefer the sounds of their 'softer' nonlinearities when they're overdriven (and it's also what they were used to).  But with suitable circuitry, modern transistor-based amps can be constructed that are sonically indistinguishable from tube amps, because they have the same gain and same non-linearities.  And with today's digital synthesis capabilities, it's possible to model just about any arbitrary audio response (transfer function) in an audio amp.   Each year, there are fewer and fewer "experts" around who claim they can still hear the difference.  
> 
> 
> As the great physicist Max Planck pointed out, "Science advances, one funeral at a time."




I'm still not sure if you guys are saying a modern transistor amp can do everything a traditional tube amp can do without digital tube modeling circuitry built into it including compression and "sag" .or not.

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## xSinner13x

> I'm still not sure if you guys are saying a modern transistor amp can do everything a traditional tube amp can do without digital tube modeling circuitry built into it including compression and "sag" .or not.


I think that is indeed what I was driving at hence the inclusion of the EJ Video. :Wink: 
Also the other two major producer at the moment make an incredible product as well.
But that's neither here nor there let alone on topic...

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## Mark Gunter

Solid state electronics are far superior to electron tube electronics in practically every way imaginable. People are still free to prefer the sound of one amp over the next, regardless what amps they may be comparing. SS to SS, SS to Tube, Tube to Tube, if you hear what you can't live without in any particular amplifier, buy it and enjoy it.




> As the great physicist Max Planck pointed out, "Science advances, one funeral at a time."


So true!  :Smile:

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xSinner13x

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## DavidKOS

> I'm still not sure if you guys are saying a modern transistor amp can do everything a traditional tube amp can do without digital tube modeling circuitry built into it… including compression and *"sag"* ….or not.


Even when I used tube amps I used amps like a Fender Showman that had SS rectifiers, I cannot play with sag - I want the amp to respond to my playing and not lag behind.

Some of the best modeling amps may well have some sag - like I said, I avoid it  so I do not know.

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## Wes Brandt

> .I want the amp to respond to my playing and not lag behind.



You just have play a little ahead :Wink: ....

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DavidKOS

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## Wes Brandt

> Solid state electronics are far superior to electron tube electronics in practically every way imaginable. People are still free to prefer the sound of one amp over the next, regardless what amps they may be comparing. SS to SS, SS to Tube, Tube to Tube, if you hear what you can't live without in any particular amplifier, buy it and enjoy it.
> 
> 
> So true!



You left out the part about the interpretation of what is "good tube sound", or "style" by the engineers.. which will vary...

I use SS myself, a true stereo keyboard amp and rely on ...multi FX boxes for all modeling, including fake tube sound.  I just like arguing. :Wink:

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## Mark Gunter

> You left out the part about the interpretation of what is "good tube sound", or "style" by the engineers.. which will vary...
> 
> I use SS myself, a true stereo keyboard amp and rely on ...multi FX boxes for all modeling, including fake tube sound.  I just like arguing.


I use a decent programmable modeling amp myself. And I sometimes play the devil's advocate as earlier in this thread - it can be educational, at the risk of having folk confuse you with the devil though.

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Bernie Daniel, 

DavidKOS

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## HonketyHank

Amps? What's an amp?

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Timbofood, 

xSinner13x

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## sblock

We seem to have wandered well off the topic.  The pickguard (or finger-rest) is not in state of "demise," by any stretch of the imagination. It is alive and well, and it works for a great many of us.  And it does not detract from the sound of the mandolin.

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Mark Gunter, 

Timbofood

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## Petrus

In addition to the mini-pickguards shown a few pages ago, if looks are an issue, how about a transparent one? If you feel that sound is an issue, how about one with perforations in it?

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## Bertram Henze

> ...how about one with perforations in it?


The material exists...

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Rick Jones

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## David Lewis

> What I hear is proof for me. Science proves something today then something different tomorrow so I can do the same thing. Prove the cat is dead today and maybe it's alive tomorrow. All kidding aside how do we really prove the things we have been talking about, a lot of knowledgeable people have stated slightly different proofs. Probably all are correct as for as it goes, but come on we are talking art, how do you prove art.


The cat thinks it's dead.

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## Bertram Henze

> ...we are talking art, how do you prove art.


Oh brother we're art, though. Love it, don't prove it. See* what I mean: we hear different things.

(*) pun intended

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## Mark Gunter

> In addition to the mini-pickguards shown a few pages ago, if looks are an issue, how about a transparent one? If you feel that sound is an issue, how about one with perforations in it?


I think the general consensus is that sound is not an issue with pick guards. At most, the player might detect some small differences in sound, but within a few feet of the instrument it is doubtful any difference will be noted with or without a pick guard. It seems that at some time in the past, it was fashionable to believe that a pick guard might hinder projection, but that apparently was a myth that has, for the most part, been dismissed. At any rate, players are free to make their own choice as to aesthetics and playing style. Some use the extra plate as a finger rest, some don't. Some like the looks of it, some don't.

If you try the rabbit cage wire, be careful not to get your pinkie caught in the perforations.

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## sblock

Markscarts has it right.  It is totally unnecessary to develop some type open or perforated pickguard (finger-rest), because, due to its location, size, and physical properties, the existing generation of pickguards is -- for all intents and purposes -- acoustically transparent!  Put simply, we do not need to produce perforated pickguards, or ever-smaller ones.  If you think an optically clear, acrylic one looks better on your instrument, fine, but this is an aesthetic choice, and has nothing to do with acoustic transparency.

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## sunburst

> Put simply, we do not need to produce perforated pickguards, or ever-smaller ones.


So, you're not much into _marketing_ either, I see...

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## Mandoplumb

> Oh brother we're art, though. Love it, don't prove it. See* what I mean: we hear different things.
> 
> (*) pun intended


I am an artist as are any musician, maybe there is a technical "proof" but in reality that point is mute. Beauty is in the eyes of the beholder. Prove your wife is more beautiful than mine, or maybe vice-versa. LO

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## Timbofood

I had a clear one built for my Stiver, worked very nicely. I wonder how that one has held up, should have kept it! Should have kept them all!

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## Mark Wilson

> Should have kept them all!


Seems like everything musical I have parted with has resulted in a 'wished I still had that' moment.  With the exception of some cheaply produced gear.

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Mark Gunter

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## Petrus

> So, you're not much into _marketing_ either, I see...


Like the Model T Ford ... you can have any color as long as it's black.  :Laughing: 

Anyway, no discussion of pickguards would be complete without mention of the innovative Epiphone pickup-in-pickguard configuration:






> Rather than loading down the mandolin with electronics and adversely affecting its natural acoustic tone, the Shadow system puts all the electronics inside the pickguard. This allows the Epiphone mandolin to respond and sound just like an acoustic mando should. On the pickguard are master volume, treble, and bass rotary controls, as well as an easy-access battery compartment using a lightweight, long lasting 2032 watch-style lithium battery. Even the pickup is mounted on the pickguard.


http://www.musiciansfriend.com/folk-...ctric-mandolin

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DavidKOS, 

hank, 

Timbofood

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## MikeEdgerton

> Anyway, no discussion of pickguards would be complete without mention of the innovative Epiphone pickup-in-pickguard configuration


That's not really a new idea, it's been around in different forms for decades in the guitar world.

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DavidKOS

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## blindsay86

That is one of the most beautiful mandolins I have ever seen.

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