Well, that's interesting....

[Randall]

Was playing one of my recent 5E3 builds and noticed a buzz on the low E note from a Les Paul. Poked and traced until I found a mechanical vibration on the left side of the G-10 turret board. Found nothing loose. Board is secured by two spacers ala Triode, one screwed in about 2/3 to the right at the top, the other about 2/3 left at the bottom of the board.

What I discovered was that the end of the glass board was resonating enough at that frequency to vibrate a little through the chassis, and then into the cabinet, which amplified it a bit. Also, I used solid core cloth wire, which I also discovered was part of the issue. The way I had run some of the leads from that end of the board had contributed to transmitting or resonating that frequency by being flown rather than pushed down to the chassis. All of this combined created a perfect symphony in E.

I was able to damp it by simply snugging a few of the wires up against the board and chassis on their way to tube sockets, ground, etc. I believe this changed the resonant frequency of that sub system and solved the issue.

Which got me thinking... I wonder if that would have been the same issue with stranded wire? I'm thinking probably not, as stranded would be more likely to absorb/damp vibration rather than transmit it like a solid core wire in the air.

make any sense?

[xtian]

A new dimension in lead dress! We'll start measuring our wires in thousandths of an inch instead of gauge. You really shouldn't use 0.042 wire where there's a possibility of a low E.

[Randy Magee]

I would have chased my tail a while with that!

[M Fowler]

Nice work Randal finding the problem.

On my 5E3 the board covering the chassis vibrated so had to put some flat washers under the finish washers to get the board to fit tighter.

Without the flat washer, the finish washer cut into the tweed covering not allowing it to tighten. I always use the additional flat washer, otherwise, the finish washer will really cut into tolex material.