C string - D and D#/Eb problems

Question: In general, are D and D#/Eb (C string - second and third fret, respectively) less resonant pitches than others on the ukulele?

Problem: I have noticed this problem on two KoAloha tenors and a Fluke. Because the KoAloha and Fluke are extremely different in design and materials, I am wondering if is a common problem for ukuleles.

Playing: The problem is not so noticeable while strumming, but when picking, the difference in tone quality between pitches can be quite frustrating.

Try lower tension strings or drop tune it... high tension usually does that...

Common issue with stringed instruments. Some call it 'wolf tones'

I read that from the violin family to ukuleles, this happens, usually most noticeable on lower pitched strings.

Has to do with instrument resonance, cavity size, tap tone frequency....etc.
If you do a search, especially on acoustic guitar forums, you can find a lot of threads about this.
Good luthiers attempt to avoid this by using bracing, top/back thickness, sound hole size ...etc...
to try and get the resonance point to fall between in tune notes. ie half way between say D and Eb.
This reduces the severity of the wolf note by avoiding its strongest node.

Searches can help you understand it. Helmholtz frequency is another version described as a cause.
One way to also diagnose this, the insturment may convey a stronger vibration sensation when these
notes are played. Somehow the combined parts, body, neck, airspace inside, work against the note,
and cause it to decay faster and sound thudddy.

I have sold well respected factory guitars that did this more than i could accecpt.

My Pono PT tenor, (one of the early ones) did this centered on D played on the C string (like yours)
A little brace shaving, after lots of study and acceptance that i might ruin it, I tweaked my Pono a little
and got the worst improved. Now tone centers between C# and D, so stilll have it on two notes now,
but not as bad as before..
Dont try this at home without understanding or at least accepting the possible consequences.

Hope this is helpful.

Thanks for the replies.

I have read, searched, and even studied acoustics of musical instruments in grad school, and have a basic understanding of the problem. However, "fixing" the problem is not something I would attempt myself. Believe me, adjustments would be done by a professional.

At present, I am trying to determine whether my expectations are too high (i.e., expect no problematic pitches direct from the manufacturer), even for a high-end instrument. Or, since I have experienced very similar problems from two of the same make/model, to expect to have a luthier.

I am positive that the manufacturer will continue to work with me, but I do not wish to continue returning instruments, if my expectations are unrealistic.

Thoughts?

It's possible you might be making the problem worse by how you hold the instrument. It's best to avoid clinching the body in a death grip as you usually end up putting pressure on the top behind the bridge when doing so...

Just something worth checking.

Bill1 said:

If you try to play your uke like a guitar around the 7th fret where the C# D D# are on the g string, I suspect you will never get the same type of resonance on the uke as you would be used to on your guitar. There is also a big difference in the length of the sustain. It is probably unrealistic to expect the D on a uke to ring as long as the D on the guitar. Probably it has a lot to do with the relative sizes of a uke body and a guitar body and the lengths of the strings.
The three notes you discuss are the lowest notes on the re-entrant uke, if you look at the various traditional style of ukulele playing you will notice the use of low G tuning to get lower notes, and/or the use of playing styles that compensate for the relative lack of sustain and the re-entrant tuning characteristics.

Click to expand...

Bill, I did not mention the 7th and 8th fret of the G (Low G on my Uke), but indeed, the 8th, in particular, has a decay of about 1.5 seconds, compared to the open Low G of about 4 seconds. The comparison I am making is that of using the open string as the standard of tone and resonance. The tone and resonance of all other pitches are compared to their respective open string.

Subjectively, the open strings sound gorgeous. Objectively, all open strings have a decay of 4-5 seconds (to the ear). I am sure that this is why the 7th & 8th fret on the Low G sting, and 2nd & 3rd fret on the C string sound somewhat offensive.

Thank you for testing your instruments, and informing me as to your findings.