I just ran into a problem I've never had before. When I plugged my guitar into a regular sized amp (as opposed to my 9 volt Honeytone amp) everything sounded fine when the volume was turned all the way up but when I turned the volume down, a very annoying hum popped up.
As in all my previous builds, I had parallel piezos wired in with a volume pot. I used an inexpensive 1 M pot from Gitty and I thought that might be the problem. I used two wires twisted together as I had in other guitars for all the wiring. I replaced the wiring with a shielded coax wire and that buzz totally disappeared.
Anyone have any guess why I would have this problem now when I never had it before. (I did plug in all the previous builds that I still have and none of them had that problem.)
Replies
A bigger AC powered amp is going to be more sensitive to RF noise from a hollow bodied git. This is why the shielded wires fixed the problem. I've started using this kind of wiring for my CBG's. If you don't have access to this kind of wiring, twist the negative and positive wires together from the jack up to the volume pot.(not meaning to connect the 2 wires, but wrapping them around each other while still being insulated from one another)
Lining the inside of the box with aluminum tape, copper tape or shielded paint is also a great idea for keeping the noise down with piezo's and single coil magnetic pickups.
Thanks. I always ground the case. Actually, when I first wired this guitar, I had a huge buzz then realized I had mixed up my wires and grounded the outer ring of the jack instead of the inner ring. I swapped the wires and that took care of that problem. It wasn't until I plugged into a full amp that the volume turned down buzz popped up.