Setup Buzzing after string change

[Pissodes]

I changed the original strings on one of my ukes last night. The strings were fine, just wanted to try something different.

I immediately notice a higher pitched buzz/rattling sound on the second string. I had not noticed this before. It starts an stops quickly went the string was strummed and picked. Not noticeable on light to medium strumming. The string buzzes only when the string is open. Fretting at the first and up the neck has no buzzing.

No other strings buzz. This uke was professionally setup by a very reputable uke shop.

Things I did to assess the issue:
-New strings are a thinner gauge that the originals. I tried a thicker gauge string with no success. I put the originals back on with no success either.
-Tapped the body, but nothing sounds loose. There are no pickups in/on this one.
-Boroscoped the body but nothing appears loose.
-Tightened all the tuners.
-I placed a piece of paper under string at the nut.
-Placed a 0.5mm shim under the saddle.
-Checked the action at first for this string and it is close to 0.20mm. The other strings are 0.25mm.

I know that any string can buzz if you try hard enough, but this one is odd as I don't believe I'm playing it any hard that the others.

The only thing I can really think is that the slot was slightly overcut and the string is hitting the first fret when strummed hard.

So, before I look up specific methods on packing and recutting the slot, what else should I consider doing?

 

[man0a]

Does the string buzz when played open as well as when fretted?
Can you tell if the buzz is coming from nearer to the saddle or nearer to the nut?

 

[Pissodes]

Only buzzes when played open. No buzzing when fretting the string at the first and up the neck. Buzz sounds like a baby rattle.

The buzz sounds like its nearer the saddle. I can't really determine what would be causing that which makes me think I'm hearing something that's traveling down the string to the largest resonating part of the uke.

The buzz only lasts a fraction of a second right after being strummed.

 

[Patty]

I might have a suggestion, @Pissodes. Does the tuner on your second string look like this? (Note that the upper part of the tuner is leaning toward the string, creating a visible gap). First picture is the tuner by itself; second picture is that tuner in relation to others, so you can see the difference.

If this is the case, I can tell you how to proceed.

 

[man0a]

Only buzzes when played open. No buzzing when fretting the string at the first and up the neck. Buzz sounds like a baby rattle.

The buzz sounds like its nearer the saddle. I can't really determine what would be causing that which makes me think I'm hearing something that's traveling down the string to the largest resonating part of the uke.

The buzz only lasts a fraction of a second right after being strummed.

Only buzzing when played open tells me the buzz has something to do with the nut or the tuner or the way the string is tied to the tuner. If this string is thinner than the previous one and there is not enough tension at the nut, the string could be rattling in the nut slot. I'm told this happens most often with the C string, but I assume your "second string" is the E string. If you only wound the string around the tuning post a couple of times, you can increase tension by winding down the post 4 or 5 times so the string approaches the nut from a lower angle.

Loose screws/nuts at the tuners can also cause this problem, but you did say that you tightened all the tuners.

 

[Pissodes]

@Patty The tuners are flush to the peghead. I did remove the tuner and reset it as part of my cause assessment. I gave all tuners a good half turn with a crescent wrench to ensure they are tight.






@man0a Your are correct, this is the E string. These are the original strings back on the uke so no change in gauge. Unfortunately, this string almost as low as it will go on the tuner. This a Millar that is using Der Jung tuners. These tuners are meant for heads 11mm or less in thickness where this is 12.1mm. The result is fewer possible wraps. The peghead angle is fairly steep though so the break angle seems pretty adequate.

 

[modwitch]

No helpful tips, just thanks for posting your troubleshooting process. I imagine I will run into this issue at some point!

What kind of bridge is it?

 

[TerryM]

Have you tried thumping the tuner without a string wound on it? I know you reset it, but thinking maybe loose gears.

 

[man0a]

All I can say is that if it wasn't buzzing with the original strings and it is buzzing now that you have re-installed the original strings, the only change sounds like the way the strings are installed.

 

[Pissodes]

No helpful tips, just thanks for posting your troubleshooting process. I imagine I will run into this issue at some point!

What kind of bridge is it?

Its a very small slot style bridge.

Have you tried thumping the tuner without a string wound on it? I know you reset it, but thinking maybe loose gears.

Im considering moving the tuners around and seeing if the issue follows the tuner.

All I can say is that if it wasn't buzzing with the original strings and it is buzzing now that you have re-installed the original strings, the only change sounds like the way the strings are installed.

Its totally possible. You can see in my pic that there is extra string sticking out from the tuner. These strings were initial cut flush to the post so I have managed to get fewer wraps on the post based on my tying technique. These are Worth browns which I have on hand. May try fresh strings too.

 

[PTRarch.]

If the nut was cut on the limit, like you suspect, and your new strings have different (lower) tension, thus a different (higher) amplitude, it could be that the string can hit the first fret, and that the string "calms down" after that first hit and takes a slightly lower amplitude but keeps on resonating.

Did you re-use your old strings? Since they have been stretched on the initial install, been under tension for X time, then released (unstrung), and then put under tension again, they could have taken another stretch, with again, a change in tension thus amplitude. So you cannot really compare them...

Part of the typical elastic modulus of plastics (as defined in carbon or organic chemistry) and Hooke's Law.

And you had the same problem with a slightly raised nutslot (the paper trick)?

Did you try putting in some pencil lead? Stiction can do strange things to your nuts (@Voran and @SkeeterAB: this one's for you! )

Slot style bridge: knot seated well and not a dangling piece of string that's hiding somewhere?

(Just thinking out loud here... I chasing buzzes - even when they're not mine )

It's not easy diagnosing these things remote, not hearing or feeling the buzz. It's like when the doctor says you need a colonoscopy, and you fax him a picture of your butt. If you get what I mean...

 

[Wiggy]

SWAG: Do the strings you put on have significantly less tension? It's possible that the neck relaxed and back-bowed a very tiny amount, reducing clearance at the 12th. If your clearance at the first fret was very low to begin with, buzz may result.

Check the clearance at the first fret by holding each string down between the 2nd and 3rd fret, then (while holding it down) look at the clearance between each string and the top of the first fret. There should be at the very least "some," no matter how small.

 

[PTRarch.]

You mean bowed down (lower tension decreases upbow and results in less relief in the neck).
But you're right, could be. And I forgot that one...

There's a lot that can happen with just 1 action (changing strings), you get a bunch of interactions and consequences, maybe every single one quite miniscule, but added up just enough to drive you nuts ...

Clearance at the first fret: holding down on the second you should be able to pass a piece of paper.

And maybe wait until the string is settled in, before you change anything drastically. It might still need a little stretch...

 

[pondweed]

does it go away with two pieces of paper in the nut slot? three?

 

[PTRarch.]

Fretting at the first and up the neck has no buzzing.

New strings are a thinner gauge that the originals. I tried a thicker gauge string with no success. I put the originals back on with no success either.

That should narrow it down to:

• It's not the string;
• It's between the first fret and the peg (including the peg).

 

[Wiggy]

You mean bowed down (lower tension decreases upbow and results in less relief in the neck).
...
There's a lot that can happen with just 1 action (changing strings), you get a bunch of interactions and consequences, maybe every single one quite miniscule, but added up just enough to drive you nuts ...

Clearance at the first fret: holding down on the second you should be able to pass a piece of paper.

A piece of paper is about .003" and that is a good target. What I meant was, as little as .001" will likely work. There just needs to be "some" clearance, otherwise you can't measure it.

- - - TMI (but somewhat related)
Not pertinent to this discussion, but if one lowers the saddle height, that also will decrease clearance at the 1st fret. Geometry.

 

[PTRarch.]

I only tried to clarify what that "some" should be in a relatively "measurable" layman's term, or measurement in this case.
I normally use feeler gauges. In mm. I keep that between 0,06 and 0,075. But that's about paper-thick so there you go.
So: I concur.

I did not so on the bow / relief point you made . No offence taken I hope, not intended in any case.

Just trying to chip in...

 

[PTRarch.]

Geometry.

You mean trigonometry?

 

[Wiggy]

You mean trigonometry?

I'm 75. It's been a long, long time...
I never knew what the "tri" in trigonometry meant. So, in a basic sense, you are correct!

"Trigonometry is the study of properties of triangles, especially right triangles. But geometry is the study of properties of all the geometrical figures."

So why weren't we taught trig first? It would have made things so much easier.

 

[Pissodes]

Thanks all for the input. I believe I know the answer and it is the sting is hitting the first fret.

I moved the string aside and ran a dry erase marker over the fret. Carefully placed it back and strummed it a bit. After moving the string aside again I could see the string had removed some marker. Just a little, but enough to cause the light buzz. Kinda surprised that putting the piece of paper under the string in the slot didn't identify this before.

So now the question is file the fret or rebuild and recut the nut slot..?