I ran into a problem with a wound bass string once. There was a bit of a buzz which I tracked down to a broken winding. See the attached photo.

I identified the problem when I ran my finger up and down the string. It was visible to my naked eye once I knew where to look.

A simple string change fixed it.

I have found that the first strings to 'go dead' and sound crappy are usually the wound strings.
The easiest course of action here (pun intended) is to simply put on a new string and see if that solves it. I know that having extra strings and putting on a new string can be kind of a big thing to new players, but it's pretty routine for experienced players of stringed instruments. (not saying I do it all that often... i don't ) 
Chances are a new bass string will sound nicer for you no matter what the issue is right now. Think of changing the string as similar to giving yourself a new toothbrush- you don't necessarily 'have to', but it's not expensive to do and may give you good results.

P.S. do you know what gauge strings should go on your dulcimer according to its scale length from nut to bridge, and the tuning you usually play in? And do you have extra strings?

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Site Owner

Those irritated by grain of sand best avoid beach.
-Strumelia proverb c.1990
updated by @strumelia: 04/11/25 09:11:06AM

Specifically with the language of tinny, My first guess would be that the strings are not seated correctly in either their slots at the bridge, or their slots at the nut.

updated by @nate: 04/11/25 02:28:07AM

Hi @mdwannabe.  First, strings get stiff and stale just from exposure to air.  They also get grimy from being played, but strings age even if they are not played at all.  And wound strings age much faster than do plain steel strings.  So you might consider just changing your string.  Try that before anything else.

I am not sure what exactly you mean by "tinny."  Is there perhaps a buzz?  If you fret the string, does the "tinny" sound remain?  Try fretting at each fret and see if sound gets better.  If it is equally tinny up and down the fretboard, perhaps it is not sitting cleanly in the nut or bridge and a small adjustment might be necessary.

I'm sure one of the builders here at FOTMD will have better ideas than I do.

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Dusty T., Northern California
Site Moderator

As a musician, you have to keep one foot back in the past and one foot forward into the future.
-- Dizzy Gillespie

I have a June Apple Dulcimer that played really well when I got it but I took it out again and the bass string has a horrible tinny sound when it is played. I don’t think it has been played enough to need new strings.