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My last guitar is my best so far, but 12th fret low e string is lacking compared to everywhere else. 2 frets up it sings, 2 frets down it sings. I've heard Greg Smallman can put a piece of putty on the soundboard in the correct spot and change such notes.
My thinking goes along these lines.
Sprinkle glitter or some such over the soundboard play the offending note, see where it accumulates, place the putty in the spot, see if it changes for better or worse, either add or subtract from that spot gradually depending on any improvement.
Can anybody help?
Ray

Are you positive it is not a fret problem? Seems to me if "E" was a problem note you would get a similar result at any "E" played. You should definetly get the same problem with "E" as played on fret 2 of the D string, it's the same note as low E at the 12th.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Putty can be a good tool to sort these sort of things out....

As B Howard points out, though - make sure it isn't a fret problem... You should be able to play that 12th fret "E" on 2-other strings..... If it isn't clunky on those strings - suspect the fret...

Another idea.... how about just playing it a lot... Frequently - a freshly strung instrument may have a clunky spot somewhere aggravating - but after several hours of playing, it loosens up and the clunky spot moves off the note....

Somehow, 10-20 hours seems to be a number I read about a lot....

Thanks

Thanks for the replies, and sorry for my ignorance but...What do you mean by a fret problem?
It seems to be seated properly and all the other strings played on the 12th sound fine. The D string 2nd fret sounds fine. The guitar has been finished for about 3 months, spent a week on the Tonerite and has been played since but has always had that one weak spot, it's nothing I can't live with, when does it really ever get used anyway? but it just bugs me that it's there.

Maybe the tonerite did you wrong.

What we are getting at.... If it is a "Wolf Note" problem - where something in the instrument is vibrating sympathetically with the specific note.... it will happen whenever you play that specific note.... on any string.... You can sometimes track that sort of thing down by playing the specific note through a speaker and find the place that starts humming/squealing/vibrating like crazy....

If it doesn't go "clunk" when you play the same note on any other string - there's a good chance it's some specific problem related to that specific fret or the nearby frets....

One example - if a fret is a bit too low compared to the next fret - it may not buzz... but the string may hit it and become damped...

Thanks

Couldn't you raise or lower the pitch of the string and play it in the same place to answer some of these questions?

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Jim Hansen

That 12th fret E note is at 164.8Hz which may be too close to the main top resonance. Check it with spectral analysis. What you need to do is try to shift that resonance up or down so it falls between scale notes. Additional mass added to the top on an anit-node will lower the top resonance but may also effect the body and other resonances so you have to check the results. Alternatively, if you have room, you could reduce the mass of the bridge, use lighter bridge pins or both to raise the top main resonance a few Hz.
To get a handle on this stuff get the Gilet/Gore books. As they say on the back, "Until you have read this book, you cannot have a fully informed conversation about guitars".
Cheers
Dominic

G'day Dom,
Thanks for that, and thanks to everyone else. I raised and lowered the string pitch and the 12th came to life, I guess that means a wolf note.
How much are we talking about off the bridge Dom, I could maybe get a few more grams off but there is not much left to play with.
Will that change it to a different note as altering the soundboard may do?
I have been thinking about the Gore/Gilet book but all the math and physics put me off. I got Somogyi's set and that was verbose. I don't suppose you know if they have a "guitar building for dummies" do you?

As you raised or lowered the string tension, did the problem move to a different fret? It should have stayed relative to the approximate 165 Hz mentioned earlier. But as that note rang true when played on other strings, i still don/t think it is the problem. Changing string tension causes other changes in the system. A change in tension will alter neck relief, will alter the nuts relation ship to the bridge, alter the bridge rotation and height above the soundboard. Not to mention the effect on the strings vibrational modes. Yes all these changes would be in fact very very small, but it would not take much change in just neck relief for example to get a string to play clean over a fret that was maybe 0.001" high. Have you checked your frets with straight edges along that strings line? Not just a long one, but a short one that only spans the 3-4 frets in question. This area of the fret board is also real close to the body joint, a small hump at the 14th can cause something like this as well, though usually across all strings. Before you commit to shaving down and altering components, try shimming the saddle bone up 0.020 or so and see if the problem persists to be sure it is not neck related. Remember you can take wood off fairly easily, putting it back on is a lot more difficult.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Hi Brian,
Yes, when I raised it up to a G the E played on the 9th fret was lacking and when lowered to a D the E played on the 14th fret was lacking, but I know what you mean, it's a bit of a worry to go messing with it now, one slip and it's goodnight charlie.

E=164.8 Hz seems low for the 'main top' resonance, and high for the 'main air'. There are a couple of things that can happen an octave above that, but that would usually effect the open E string. 'Wolf' notes can be exasperating to track down.

Not if the guitar is an underbraced dreadnought. I have witnessed top resonances as low as a "D". In most cases, those guitars are way too bassy for my taste.

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John

I assume we are talking about a classical guitar here since Smallman was mentioned. Even if you aren't, I wouldn't go shaving wood anywhere. It's a lot easier to get some poster putty and move a wad of it around the top until the wolf note goes away. This may take a while and it might take more than one wad. When you find the solution then play the guitar and make sure that you haven't caused any other problems. If you haven't, then glue a piece of wood of equal mass to the wad under the soundboard where your wad is. The only problem with this is that you may be on a brace.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

OK, so 164Hz is not low if we are talking about an under braces dred, or a wet piece of cardboard, but generally this is on the low side, particularly for a classical guitar if that is what we are discussing.

And the problem with adding weight to the soundboard is that your fix makes the soundboard less responsive and reduces volume. So I was suggesting trying other fixes first before reducing the efficiency of the soundboard. By reducing mass on the soundboard you may be able to raise that frequncy enough to avoid the wolf note and get a more responsive guitar. Of course the coupling effects means you may also change the main air resonance so you have to be careful as Alan hints at, you can create more problems for yourself on another note. Just seems worth pursuing that route first before going the other way.
Cheers
Dom.

Using the lump of putty makes sense as a tracking aid.....

Once you figure out where the putty helps - you can whittle a bit away from that spot and usually get the same response.... or if you don't like the idea of whittling away... you could also just glue a more permanent lump to the same place...

Thanks

The putty on the soundboard trick is used by Smallman because it's very difficult with the CF/balsa/CF bracing to do anything else. You can't meaningfully alter the stiffness of a brace once it's together, and I don't think he has any way of testing them as he's working. His tops are so light anyway that a small increase in mass that clears up a problem note is not too big a price.

Adding mass is often a good first step, since it tells you where the problem is. Note that adding mass in a particular spot has the same effect on the resonances as reducing stiffness in the same place. If putting a little bit of putty on some spot makes the problem go away, it's likely that reducing the stiffness there will do the same. Shaving a brace, or thinning the top, will also _reduce_ the mass, of course, and generally (although maybe not always) increase the mobility and produce more sound.

You have to be smart about this, of course: if you needed to put a big lump of putty on the X braces right below the bridge to fix the problem, that would indicate that you might have to remove a lot off stiffness there by shaving the braces down a bunch. Will that leave them strong enough? Is there something else you could do, like adding some mass to the bridge?

This does sound like a 'wolf' to me, and, as I say, those can be tricky to track down. Since it's at such an odd pitch for 'normal' top resonances, maybe it's somewhere else? The back, for example, gets all of it's energy from the strings via the top, either through the air or through the sides. It's not nearly as effective a radiator as the top, so a strong resonance of the back can end up 'stealing' energy from the top and not making much sound. Try that putty in a lot of places, and not just on the top.