Overtones on A String

[carlsonp]

Hi All:

I bought two nice instruments, each with a 48 hour return period. I'll have to decide by tomorrow which one stays.... suffice it to say my fingers are sore.

They both are really fantastic to my taste and I'm having difficulty deciding, but one of them has a pretty bad, metalic overtone on the A string, but only when not fretted. The instrument is otherwise outstanding, but this would be a deal breaker having sounding quite 'off' with an open A.

I'm hoping the deep, collective wisdom here could provide some input. I'm guessing, because the overtone is absent when fretted that this is likely a fairly simple issue with setup? Most likely the nut? I wouldn't mess with that on an instrument that may be returned, but if it's a fairly simple issue with the nut, I wouldn't let the overtone influence the decision (it's primarily on one of the A strings). Ideas?

Finally, I've played and sampled a lot of instruments, including quite a few really high end makes. That said, my sampling in stores or temporarily switching mandos in a group has been nothing like this in-depth A/Bing experience.... really fun switch back and forth for hours, comparing the fret board, digging in, playing light, different picks, etc. An amazing experience. Assuming the overtone is not a big issue, it will be tough to send one back as they both have outstanding qualities. I'll be glad to share the experience.

Thanks for any input.

Peter

[CarlM]

I recently had a loose truss rod nut give me a buzz on one open string. It was a pain to track down because being only on one open string that was the last thing I suspected. Tightened the nut and it went away.

[pheffernan]

I'm hoping the deep, collective wisdom here could provide some input. I'm guessing, because the overtone is absent when fretted that this is likely a fairly simple issue with setup? Most likely the nut? I wouldn't mess with that on an instrument that may be returned, but if it's a fairly simple issue with the nut, I wouldn't let the overtone influence the decision (it's primarily on one of the A strings). Ideas?

People have been known to use a piece of paper as a temporary fix for a nut slot cut too deep, which might be enough to evaluate the instrument. A more permanent solution involves baking soda and CA, though I wouldn’t attempt that on someone else’s instrument. The ultimate answer is to replace the nut if and when it becomes your mandolin.

[soliver]

Is it possibly a sympathetic vibration between the nut and the tuning peg; or possibly between the bridge and the tailpiece? A lot of folks use the little black grommets for that, I prefer a woven piece of leather.

My SA makes some extra noise sometimes. When I strike certain notes, sometimes some other strings will hum sympathetically as well. I've grown accustomed to it and can usually compensate.

[Eric Platt]

Agree with it likely being sympathetic vibration from the string to nut, or bridge to tailpiece. Also a slight chance it could be the tailpiece itself. My Flatiron has it around the same note. If it is a Gibson style tailpiece, take the cover off and see if the sound persists. If not, that's the source.

Good luck in your decisionmaking.

[carlsonp]

Thanks for the ideas, everyone.

So far I've checked the truss rod cover (screws were tight), loosed the string a great deal and brought back to pitch, and raised the treble side of the bridge a half turn. It does go away when holding the sting between nut and tuner post, nor if I lift the James tailpiece.

It does seem like it's diminished somewhat since receiving it (the strings showed zero sign of play wear upon arrival... I'm guessing it was received by the shop just before of even after all the business closures occurred) and the E sting also had this slightly, but now that's gone. The overtone isn't a higher frequency overtone that one sometimes hears between the nut and tuners, and not exactly buzzing either, but rather a change metalic tone within the note, if that makes sense. I hear it more when playing an open D cord than playing the open A alone.

I'm all ears for any more suggestions. I'll try a little paper in the nut. Thanks again, everyone.

[pops1]

When you put the paper in the slot look carefully first under a good light and see that the string is touching the very front of the slot. You should be able to see where the string is riding on the nut, use a magnifier if necessary. If it is all the way to the edge, try the paper, if not the nut will need adjustment.

[CarlM]

Mine was the nut on the truss rod, not the cover.