The banjo in question is a custom built open-back banjo with a 27" scale, a 12" pot, Dobson tone ring. Renaissance head, Kershner adjustable tailpiece, and a compensated Grover bridge.
When I fret the 2nd string in the 3rd fret and pluck the string relatively hard (especially with the thumb or a thumb pick, it does not happen when I up-pick the string with the index finger), there is a noticeable buzzing sound. It does not happen with the open string or fretted in any place other than the 3rd fret. It also only happens when I pick firmly.
At first I thought it might be the 3rd fret wire or the nut, but then I noticed that when I mute or fret the first string, there is no buzzing. From that I gather the buzz is a result of the first string sympathetically vibrating. There is no buzz when I play or fret the 1st string in any location. It only happens when I fret the 2nd string in the 3rd fret and the 1st string is open.
The buzzing noise seems to originate from around the bridge. I've pulled the 1st string out of the notch and put it back, wiggled it, etc -- no change. Moved/wiggled the bridge -- no change. I also loosened and tightened the tailpiece -- no change.
What could it be? The string itself? The bridge? Something else entirely? I've not yet tried replacing the bridge (need to purchase one or take the one that's on my other banjo) or the strings. Those will be the next steps, but I first wanted to ask here for advice. I don't know if this is a new issue or not. It's only been recently that I started to dig into the strings harder.
I had a similar problem with a fretless banjo I made. The issue turned out to be intonation.
If I fretted the 4th string D at 3rd fret F it caused the 3rd string to buzz in sympathy as the point where I was fretting the F was producing a sharpened F.
If your banjo has fret wires then sorting the issue out may be more of a problem.
Paper pad in the second string bridge slot, tighten/loosen the head? banjered
I've cured a lot of odd sympathetic vibration/ Extra long sustain of one or more notes by playing with the head tension.
Is it possible (because it only seems to happen when down-picking) that you are somehow just barely catching the top string with your thumb or pick?
I would check the 4th fret—it may be just a little bit high in one place.
Thanks everyone for your responses!
Collegiate: It is a fretted banjo, but intonation seems consistent up the neck, including on the first two strings.
Banjered: The buzz seems to be caused by the open 1st string, but only when the 2nd string is fretted in the third fret. Also only at a specific tuning (see below). Action seems fine, the 1st string, when it buzzes, doesn't touch any frets. It does not buzz when it (1st string) is plucked, open or fretted.
GEP: There is an actual buzzing sound, much like what I'd expect to hear if a string ever so slightly vibrated against a too tall fret further up the neck, but it's not doing that. I'm not accidentally touching the 1st string with the fretting or picking fingers (pretty wide spacing too).
Ken: That was my first thought too, but it's the open 1st string that buzzes when I fret the 2nd string in the 3rd fret. But only then. The 2nd string isn't buzzing and the 1st string doesn't seem to touch any fretwire (it doesn't buzz when it is plucked). The 1st string is only buzzing when the 2nd string is fretted in the 3rd fret and the 1st string is open.
I remembered I had a spare Scorpio bridge (I bought a JD spacing and a normal spacing one last year, and only used the former on my other banjo) and installed it. No change, still happening, so it's not the bridge.
Next I changed the pitch of the 2nd string to see what happens (banjo was tuned in open-G). When I lowered the pitch of the 2nd string down to Bb, fretting the 2nd string in the 3rd fret causes no buzzing of the first string. It now happened when I played the D in the 4th fret, though it is less pronounced.
Next I tuned the 2nd string back to B, and lowered the 1st string by half a step (down to C#). Now if I fret the 2nd string in the 2nd fret (C#), the first string buzzes again.
So from what I can tell, the buzzing on the open 1st string happens when I firmly down-pick the 2nd string and fret it (2nd string) where the pitch matches the pitch of the open 1st string. It does not happen when I up-pick the string or pick more gently (not carefully, just not digging into the strings). (It does not happen when I fret the 3rd string in the 7th fret, even though this is a D as well.)
My next step is to replace the strings with a new set. Ideally I'd rather not mess with the head tension, since it seems overall fine, but this would probably be the step after an unsuccessful string change.
Edited by - Mivo on 05/20/2022 09:50:17
Long shot, but are you using light's on 1?
You could try a set of GLS PF180's or Labella 730MLE.
thor363 may be on to something here. Changing string gauge(s) may alter the sensitivity of a string or strings to sympathetic vibrations with other string(s).
Altering the head tension to help does not mean a drastic change in that tension. The sympathetic sound usually changes with a very slight tension tweak (either up or down) that doesn't generally affect the overall sound.
I located the source of the buzzing. To cover all bases, I slid a piece of very thin paper in the 1st string's nut slot, as Banjered had suggested, and that removed the buzzing. Unexpected to me because there is no buzzing when I actually pick the 1st string (open or fretted). Only when the string vibrates sympathetically when the 2nd string is plucked (and only downward toward the 1st string).
Well, this is progress! :) Is there a more elegant and permanent solution than the bit of paper? It doesn't seem to change the action at all, so am I correct in assuming that the nut slot is just ever so slightly too wide?
I'm currently using d'Addario EJ60+ ("Light Plus") nickel plated strings: 9.5, 11, 13, 20w, 9.5.
You can usually fill the nut slot with CA (high quality superglue, not that cheap dollar store stuff) then re-cut the slot a little narrower. Some people add a little baking soda to the glue to make it about the same color as the rest of the nut.
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