Moved from medium to light strings. Now I have a slight buzz

[Dan in NH]

I moved from medium to light strings on my Eastman 514. With mediums my Eastman had a nice, low, but kind of stiff action. Now that I've got lights on it I'm getting a little buzz here and there.

And the action on the strings looks A LOT lower.

As I eyeball the neck from the tail piece then neck looks very flat. I'm thinking that a slight truss rod adjustment is in order.

So I take off the truss rod cover and use the wrench included from the factory...

Looking down the neck from the headstock, do I turn the wrench clockwise or counter clockwise?

[pops1]

Counter clockwise will increase the bow. With less tension from the strings the truss rod can be looser. To check, fret on the first fret and 12th fret and look at the string height around the 5-7th frets. If the change was significant, you won't be able to notice a back bow using this method, you would need a straight edge for that. It will tho let you know if the neck is flat or has relief.

[Nashville]

Yes, when you change string gauge you need to adjust the action due to the difference in tension. For me in this situation I only needed to raise the bridge a teeny bit because the neck was straight and frets were level. But I have had occasions where I need to slightly adjust the truss rod and also slightly raise the bridge. I am not a luthier but it is possible to eyeball it and make slight adjustments to get the action you want without any buzz.

[Dan in NH]

Counter clockwise will increase the bow.

Thank you

[joh]

I would first try to identify the source of the buzzing. I've had buzzing caused by loose tail pieces, loose pick guards, loose truss rods nuts covers, etc.. And if the action looked too low, I'd try adjusting the saddle height before adjusting the truss rod tension.

[Dan in NH]

Everything was fine before I changed strings. The action was fine with medium strings. Since I moved from medium to light gauge strings then the only thing that would’ve changed would have been the neck relief, because there’s less tension pulling the neck forward.

At least that’s how it works in my head.

[Jim Garber]

Whatever you do, don't turn that truss rod adjustment too much. I believe that a quarter turn would be max. Frankly I would try raising the bridge a bit with the truss rod as last resort. And even franker... I would go back to the mediums. Were they so hard to play on?

[Crazyquilt]

As noted, this is the result of the change in tension on the neck. The necessary adjustment is string height; you do this at the bridge. There should be no reason to touch the truss rod, but if so, the appropriate metric is neck relief, not string height. Truss rods are not for string height adjustment.

[JEStanek]

It could also be your Nut slots and bridge slots are too deep for the narrower string gauges. I would say start at the bridge, as others suggest.

[Misanthrope]

I'm a relative beginner with a pretty decent Kentucky Mandolin (KM-1000), but with string tension that seems very stiff and difficult to fret properly. So I'm kind of stuck right where the OP is, in wondering whether lighter gauge strings might lessen the tension a bit, making it easier to play? I haven't tried them yet, but the lightest possible gauge that I've been able to find are some GHS .009-.032. So I'm crossing my fingers.

The string height (or action) seems to be O.K., but fretting the strings (even mid fingerboard), with medium gauge strings, is just brutal, especially when and if the strings are somewhat aged or older!

[pops1]

I'm a relative beginner with a pretty decent Kentucky Mandolin (KM-1000), but with string tension that seems very stiff and difficult to fret properly. So I'm kind of stuck right where the OP is, in wondering whether lighter gauge strings might lessen the tension a bit, making it easier to play? I haven't tried them yet, but the lightest possible gauge that I've been able to find are some GHS .009-.032. So I'm crossing my fingers.

The string height (or action) seems to be O.K., but fretting the strings (even mid fingerboard), with medium gauge strings, is just brutal, especially when and if the strings are somewhat aged or older!

Measure the string height at the 12th fret from the top of the fret to the bottom of the string. Get under a good light and be accurate. Some like 2/32, I like 1.5/32 for the G string and just above 1/32 for the E. You have to have a good setup for this action, but it plays great with 11-41 strings. Also fret at the first and 12th fret and look at the clearance of the strings, say G, around the 6-7th frets. You should have hardly any gap, if you do, you may need to adjust the truss rod. Too much relief will make it play hard. A truss rod is not to adjust action, but it has an effect and too much bow in the neck will make it play hard.

[Misanthrope]

Measure the string height at the 12th fret from the top of the fret to the bottom of the string. Get under a good light and be accurate. Some like 2/32, I like 1.5/32 for the G string and just above 1/32 for the E. You have to have a good setup for this action, but it plays great with 11-41 strings. Also fret at the first and 12th fret and look at the clearance of the strings, say G, around the 6-7th frets. You should have hardly any gap, if you do, you may need to adjust the truss rod. Too much relief will make it play hard. A truss rod is not to adjust action, but it has an effect and too much bow in the neck will make it play hard.

Pops!

Thanks so much for the thorough and detailed reply. It's very, very helpful. I'll try to get after these measurements and adjustments over the coming weekend, and I'll hope they can help.

In the meantime, Iooked over the instrument a bit further (and closer), and I will share here some added information on it. I have the proper feeler gauges and other tools to do it right, but for now, I can say that the current clearance at the 12th fret is well north of 1/16", and it does appear that there is an ever-so-slight concave bow in the neck. I've also noticed that the two knurled circular-shaped bridge height adjustment wheels, are bottomed-out, such that there is no quick and easy way to lower the bridge on the saddle itself, and that's honestly a puzzle to me, because there is still air space (room) between saddle and bridge, to further lower it, but the knurled wheels themselves are completely bottomed-out (see attached photo).

[pops1]

If I come across what you have going on, I take wood off the foot of the bridge where the posts are attached. That way you don't weaken the saddle. If you need to you could plane some off the bottom of the saddle to lower it more, but don't take any off where the saddle sits on the wheels.

[musicofanatic]

Seems to me two people here would benefit greatly from taking their instrument to a skilled experienced technician. I realize not every musical instrument retailer keeps a full time tech on staff, but if you do have access to one, a brief, cursory examination would reveal the proper course of action.

[Misanthrope]

Thank you for your response.

Unfortunately, I'm in a very remote part of the country, where techs are simply not a viable option, and personally speaking, I have the tools and experience to conduct such routine work on archtop guitars, banjos and ukes, so I'm quite sure I'll be just fine on this similar mandolin. I frankly don't see this assessment as being that complex or sophisticated.

There's only three practical ways to lower those strings at the bridge: 1) sand or shave the tops of the two saddle platforms, which would require removing the threaded metal posts, 2) sand or shave the undersides of the two arms of the bridge, and bridge bottom, which is eazy-peazy, or 3) notch each of the string grooves on the top of the bridge using proper diameter nut files.

Obviously, I'll wait entirely until the current string height measurements are conducted. However, it makes zero sense to me to have a bridge with an 'adjustable' height (by design), that cannot be further adjusted, and so, should the strings truly need to be lowered, then of those three options cited above, the one that makes the most sense to me, is #2 for obvious reasons.

Thanks again.

[pops1]

Removing the posts is easy. Simply screw both adjusting wheels on one post and tighten them together. You can now unscrew the post. You will lose less structure removing wood here than the saddle. If you get it too thin where the wheels are it will crack, yours looks not all that thick to begin with.

[Misanthrope]

Thanks Pops!

Yeah, I learned that double-nut/double-wheel trick a few years ago while working on something else, and it works like a charm! However, after reading your various posts here, I think I've been referring to the saddle and bridge incorrectly, because it appears that we have been referring to them in reverse. I've been calling the top piece (that the strings sit upon), as the 'bridge', and the curved, convex structure that seats atop the finished surface of the mandolin with bow resin (the one with threaded metal posts in it), as the 'saddle'. And so now that I've discovered that error on my part, we can perhaps reach some clarity on the best way to approach this repair.

My preference would be to remove the saddle from the bridge and not mess with the bridge or it's metal posts at all, with any and all sanding or shaving to take place on the saddle (the top piece) alone, because either way, even if I were to remove the posts from the bridge and sand/shave it's two pedestals, the very bottom of the saddle itself would still need to be sanded/shaved also, or it will bottom-out on the bridge, where that very small airspace currently exists. So in my view, why not leave the entire bridge alone, and simply sand/shave the bottom of the saddle AND the underside of it's two (left/right) shelves?

[pops1]

You can, and should plane the bottom of the saddle, but I would remove wood from the foot post to keep the strength in the saddle. It spans the gap from the posts and making where it sits smaller can weaken the saddle. I have seen several crack from that spot. I have have taken wood off the foot many times with no problems down the road.

The bridge is both pieces together, saddle and foot.

[Misanthrope]

You can, and should plane the bottom of the saddle, but I would remove wood from the foot post to keep the strength in the saddle. It spans the gap from the posts and making where it sits smaller can weaken the saddle. I have seen several crack from that spot. I have have taken wood off the foot many times with no problems down the road.

The bridge is both pieces together, saddle and foot.

O.K., so plane, sand or shave the very bottom/middle of the saddle in level fashion, but plane, sand or shave the top surface of each pedestal on the foot, rather than the left/right undersides of the saddle. Got it! And that makes perfect sense.

Thank you for the help, my friend! I hope to get after the measurements tomorrow before removing the old, worn-out strings and saddle, and should it require these added steps with the bridge, I plan on doing that Monday or Tuesday and will post my results, after changes are made and new strings are installed.

Thanks again!

P.S. - And my apologies to all if these last few posts have resulted in a hijack of this thread. That certainly wasn't my intention. I'm interested in lighter gauge strings (which was the initial focus of this thread), and I suspect that I still will be, even if these changes to the bridge and string height are required.

[Misanthrope]

O.K., so, to close-out the latter portion of this thread, I have since made the string height measurements on this little KM-1000 mandolin, and given the measurement techniques and guidelines that member pops1 suggested above, here is what I've found:

Rough calculations for strings 7 & 8 (G):

Acceptable: 2/32" = 1/16" = 0.0625" = 1.6 mm
Ideal: 1.5/32" = 0.75 x 0.0625" = 1.2 mm

My current 7 & 8 (G) strings (11/40), measure at slightly LESS than 1.2 mm
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Calculations (roughly) for strings 1 & 2 (e):

Acceptable: 1/32" = 0.5/16" = 0.0313" = 0.8 mm
Ideal: 1/32" = 0.5/16" = 0.0313" = 0.8 mm

My current 1 & 2 (e) strings (11/40), measure at just slightly ABOVE than 0.8 mm
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~

Conclusions:

Despite my expressed concerns, the bridge and string height adjustments on this particular mandolin, appear to be perfectly fine (or as recommended), with no modifications of the nut or bridge assembly required. Apparently, I just need to change out the stale, brittle old 11/40 strings (maybe try some lighter gauge strings?), toughen-up my fingertips, and stop with the whining.

My thanks to pop1s and musicofanatic for their contributions here.

Cheers!

[Misanthrope]

It has occurred to me that since the above referenced string height measurements (with .011/.040 strings installed) were within the ideal range or specifications, it is highly likely that I will still have to make these stated modifications to the bridge, in order to accommodate the lighter gauge (0.009/0.032) strings.

And for that reason, I'd be keenly interested in the opinion of the OP or anyone else who has tried ultra light gauge strings on their mandolin. How did they play? How did they sound? Etc.

Thanks to All!

[Jim Garber]

I missed all the technical conversation however… your choice of ultralight gauge strings and from the more standard mediums seems a bit extreme. Carved top instruments are generally optimized for the mediums. If you find them hard to play after proper set up then I would go to lights not ultra lights. I am guessing that the ultra lights will barely be able to drive the top and may even be way too loose to intonate properly. Those ultralights are meant for lightly built vintage bowlbacks but not for a carved top instrument like the Kentucky.

[Misanthrope]

I missed all the technical conversation however… your choice of ultralight gauge strings and from the more standard mediums seems a bit extreme. Carved top instruments are generally optimized for the mediums. If you find them hard to play after proper set up then I would go to lights not ultra lights. I am guessing that the ultra lights will barely be able to drive the top and may even be way too loose to intonate properly. Those ultralights are meant for lightly built vintage bowlbacks but not for a carved top instrument like the Kentucky.

Jim,

Thanks for your response and your insights here. I greatly appreciate it. The more opinions, the better!

What you've shared here makes perfect sense, at least in strictly physical terms, and perhaps that's the case . . . perhaps I'd be better-off with something intermediate in diameter. I honestly don't know enough about mandolins yet myself to make an educated decision on this, and that's why I've come here to the MC for advise. All I really know is, with these current old and rather stale 011/040's, the tension is just ridiculously difficult to fret, and unfortunately, in terms of commercial availability, there aren't a whole lot of options between the medium (011/040) and ultra light (009/030) sets of strings. Of course, the most noticeable difference is the diameter of the bass (G) string at .032 vs. .040., which is where the bulk of the tension is really pronounce, and I suspect that's also where the bulk of the vibration force comes from, with respect to "driving the top". In addition (although I haven't mentioned this previously), the instrument itself doesn't have a lot of volume or presence. It just doesn't ring-out with the projection that you'd expect from a mandolin.

Anyway, I guess I'd just like to hear from others (if at all possible), who have actually crossed this Rubicon in real life themselves, before I start making any changes at all, including string gauge or bridge mods.

However, once again, your advice is most sincerely valued and greatly appreciated.

[Bill McCall]

….

And for that reason, I'd be keenly interested in the opinion of the OP or anyone else who has tried ultra light gauge strings on their mandolin. How did they play? How did they sound? Etc.

Thanks to All!

Ok, I have Galli flatwounds that are .095 to .32 on one of my instruments. They are great, with low tension, but the instrument was designed for light guage strings.
And my mandolin has a 15” scale, so your string tension will be different. I believe Peter Coombe has a string tension calculator on his website.

Sonically, my Mando is loud and punchy.

Ymmv

[Misanthrope]

Ok, I have Galli flatwounds that are .095 to .32 on one of my instruments. They are great, with low tension, but the instrument was designed for light guage strings.
And my mandolin has a 15” scale, so your string tension will be different. I believe Peter Coombe has a string tension calculator on his website.

Sonically, my Mando is loud and punchy.

Ymmv

Many thanx, Bill!

I honestly don't know what it is that specifically constitutes or qualifies an instrument as "designed for light gauge strings", and despite being widely available, Galli strings in .095/.032 are virtually unheard of, but they do offer a .010/.032 set in flatwounds, that might be kinda fun to try.

However, it's an expensive experiment, because they're about $26 per set! And as you've mentioned scale length certainly matters. The scale length of my KM-1000 is roughly 14", as opposed to your 15" scale, and that would in-fact produce somewhat greater tension on the former. I believe I've also read somewhere that flatwounds strings might yield higher tension than round wound strings of the same gauge, which would obviously be counter productive.