"Plunky" B and C Notes w/Little Sustain

I have an instrument where, when it is tuned to pitch, the 2nd fret (B note) and 3rd fret (C note) on the A string sound "plunky" and do not ring with any sustain. The same notes also sound "plunky" higher up on the E string. I noticed that, as I am tuning the A string up and play those same frets, the notes do ring out with resonance. In other words, when the A string is tuned to G, the 2nd and 3rd frets (A and B flat notes) ring out fine w/sustain and the 4th fret (B note) and 5th fret (C note) are "plunky". So it is obviously not a fret issue but is apparently a frequency issue with the B and C notes.

With my playing style, this is only a problem on the A string. All of the other notes on the instrument ring out loud and have excellent sustain.

Has anyone else experienced this? Is there an easy fix? I tried 3 different types of strings to no avail.

I've had a similar "dead zone" issue on several different ukes with the B on the C string, 11th fret. When a string change and a fret dressing didn't take care of it the first time, I started to conclude that it was something to do with my technique - with my stubby little hands that's not a super easy fret for me to reach. Interestingly, on my ukes with a 14-fret join, I don't have this problem. I never could figure out how to adjust my playing style to compensate for this, and I sort of stopped worrying about it when others just couldn't hear what I was hearing.

Considering you're talking about some pretty easy notes to reach, though, I'm not sure that this will apply, but - putting it out there just in case. I don't know what the fix is; one luthier told me that for whatever reason, my strings of choice just did not vibrate optimally at that frequency - however, trying different strings didn't make much difference.

Crazy-making, isn't it?

How coincidental that there are two current threads in Tech that deal with dead spot issues, but the only fix that has been applied is to do the same thing - change strings, multiple times, with the same result.

But, at least the OP identified the root cause. Now you know what to address. How you address it, on an ukulele, is probably more of a challenge than on a guitar. I've not needed to delve in this area except once, years ago, when I (nor anyone I knew) could fix an issue with an instrument that didn't play well because of first position "funky" notes on 1 string and one tone. The resolution cost double the initial cost of the instrument.

Thanks for your thoughts. I get that "dead zone plunk" on the 11th fret of the C string too. That one isn't too bad but the A string 2nd and 3rd frets' lack of sustain are noticeable. I've tried 3 different types of strings so far.

What's your next plan?

I might stick a big wad of chewing gum under the soundboard. If that doesn't work, it probably won't get played much.

Trying to be funny aside, I might actually try attaching something under the top in an attempt to change the harmonic frequency of the top, not that I know what that means or that I know anything about harmonic frequency, if there even is such a thing.

I am having the exact same issue as the OP with a Kala Solid Mahogany Tenor that I bought new about 3 years ago. Although I don't remember it being quite so pronounced when I bought it, it is definitely noticeable now.

The only difference is that the problem occurs on the C string 2nd and 3rd frets (D, Eb) and to a much less degree on the 4th fret (E). They are just dead notes - no sustain at all, kind of plinky sounding. Even though it isn't really a fret buzz sound, I have checked the frets all the way up the neck and they are as level as I can measure with a straight edge. I can't play the notes D and Eb on a different string although I can get them an octave higher on other strings with no problem - they ring fine and true. I figured I would try changing strings - right now I have Aquila Nylguts on it and I may try some Flourocarbons or other type of strings just to see if the problem goes away.

I just re-read the OP - I think that I will try tuning that string down a step and see if the problem moves up to the 4th and 5th frets...

Nearly every stringed instrument can encounter these - it's something to do with the tone matching the resonant frequency of the soundboard (the tone you get when you tap the top) in such a way that the wavelengths cancel each other out. Hopefully someone can explain this better than me. The suggestion to use a piece of putty, gum or other such substance under the soundboard is to change the mass of the soundboard, therefore changing that resonant frequency a bit so it falls between notes.

KoaDependent said:

Nearly every stringed instrument can encounter these - it's something to do with the tone matching the resonant frequency of the soundboard (the tone you get when you tap the top) in such a way that the wavelengths cancelling each other out. Hopefully someone can explain this better than me.

Click to expand...

That's very close to an explanation I was given by a luthier, so I'd say you did pretty well!

Similar idea to putty or gum - this might be worth reading.

Geared tuning machines may add weight in the right place, rather than messing around with the top tuning. Try with a clamp or clip-on tuner first.

Of course, the Hipshots that I use can't really be considered heavy, but I'm sure they weigh more than frictions.

WhenDogsSing said:

I might stick a big wad of chewing gum under the soundboard. If that doesn't work, it probably won't get played much.

Trying to be funny aside, I might actually try attaching something under the top in an attempt to change the harmonic frequency of the top, not that I know what that means or that I know anything about harmonic frequency, if there even is such a thing.

Click to expand...

I think Oldephart had a thread with the same problem. I thought he experimented using double-sided tape and small change (nickel, penny, quarter?) to fix it. Once you know what work, glue on the inside. There is even a professional luthier service to address this: acoustic blueprinting http://www.mandovoodoo.com/

I've also experienced the thunky, quiet notes on an A string before, and changed the tuning of the uke up or down a step to keep it from bothering me.

Thanks to everyone for the interesting reading and ideas. Evidently, this is a commonly experienced problem with stringed instruments. If I come up with a solution, I'll let everybody know what worked.

I'm not so sure I would describe it as common as much as I'd call it "known".