I just made a box to control the reverb and equalizer on my Mesa Studio Pre. I first ran a stereo cable out of the amp and used some wire to figure out what was what. I then wired it all up.
Here's a drawing of how it's wired using two DPDTs:
(http://poetryinflames.net/switch.gif)
The problem is that there's a distinct hum coming from the amp when I plug it in. It does switch correctly, but there is a loud pop each time I press the switch. I used the same kind of switch to control the rhythm/lead channel and there is no hum or pop. When I unplugged the pedal with the amp on, it popped and then the hum went away.
Any ideas? Is there some sort of ground problem?
(btw, hi)
The switches are correct, but the drawing of the stereo jack is very ambiguous. Just double check all your wiring again.
The socket itself may also be a switching type, as the reverb line is active when open circuit. That's a strange one if you ask me!
Another trap is when you don't quite insert the plug all the way into the socket.
Thanks for the tip. I took the dremel to the case to eliminate the ridge the stereo jack was resting on. It still made noise...then I discovered I had wired the ground between the switches incorrectly. It was shorting the EQ to the Reverb when the reverb was activated, causing a hum and loud pop. I'm fixing it now. Hopefully this does it.
Hi, i need a footswitch for my church's amp( yamaha GS-100), wondering if the diagram can be used for me to switch from channel A to B and vice versa?
Pls help..i have 3pdt switches, can use right? with LED?