resonator buzz - harmonic resonation

[WayneF]

Hi - my son just bought one of those Gretsch Alligator resonator guitars and its pretty nice for an off the shelf new inexpensive one but the resonator makes a kind of buzzing sound around 490 Hz (e.g. open B string or fretted B on the G or D strings). Because when I hold down the resonator the buzz goes away. The other notes feel and sound fine.

I assume this is some sort of harmonic distortion b/w the resonator and this frequency someone know how this sort of thing can be fixed?

Thanks

Wayne

[Howard Klepper]

Lots of possible causes. First thing I'd try is rotating the resonator to find a spot where it sits better on the flange in the body. You can rotate the biscuit to compensate. Once you find the sweet spot for the resonator cone to sit (that will probably be the cure), mark it on the cone and body (under the cover, where it won't be seen with the cover on).

You may need more break angle for more down pressure on the cone. That is a bigger deal to change.

And of course, make sure all screws are snug.

[clintj]

StewMac has nicely written directions for setting up a resonator guitar on their website. Mine sounds considerably better after being adjusted and restrung. Might be worth going through just to rule out a setup problem.

[WayneF]

Howard - so just to be clear. The resonator is held down only by string pressure through the bridge and the biscuit? So we need to unstring it, take the top plate off, rotate the resonator randomly, put it back together and try it out; and if that's not right, go at it again? Sorry this construction is new to me.

Thanks - Clintj I'll look at that for setup but the fact that its the same frequency on different strings suggests more what Howard suggests - but thanks.

[stormin1155]

If he bought it new from a dealer, I'd take it back and have them fix it.

[Long Jon]

You may be able to rotate the cone by completely slackening off the strings, without removing the cover plate.
Then some trial and error. Sometimes only has to move a few degrees. Still a PITA but possibly do-able.
Good Luck.

[Howard Klepper]

Originally Posted by WayneF

Howard - so just to be clear. The resonator is held down only by string pressure through the bridge and the biscuit? So we need to unstring it, take the top plate off, rotate the resonator randomly, put it back together and try it out; and if that's not right, go at it again? Sorry this construction is new to me.

Thanks - Clintj I'll look at that for setup but the fact that its the same frequency on different strings suggests more what Howard suggests - but thanks.

Yep. You have it. The cone just sits there, unscrewed, on the flange in the well of the guitar. And since the flange is just some bent sheet metal, it is not perfectly flat. Sorry to say, adjusting a reso guitar can be tedious. But you don't need to put the cover on and take it off again while looking for the best spot for the resonator cone to sit. Just tighten the strings with the cover off. You can try gently tapping with a fingertip around the rim of the cone as you rotate it with the strings off--you may find a spot where it gives a better, cleaner tap as you go around, and that is likely a good location for it. When you get the best sound, loosen the strings enough to pop them out of the tailpiece and put the cover back on. A marking pen will do just fine for aligning the cone with the well and flange. If the biscuit doesn't rotate easily, lift the cone out and loosen the screw a little bit. Then tighten again a bit when you have the biscuit aligned and the cone aligned. Don't overtighten that screw that holds the biscuit to the cone--two fingers on a small screwdriver is enough.

Did I say this can be tedious? But you should only need to go through it once.

There are a couple of resonator guitar forums where you can get more advice--probably better than mine.

[Mooh]

Good advice above.

Also check to make sure the ball end of the strings aren't lightly touching the cover. My resonator bass suffers from that a little so a piece of leather between them was the solution.