Info help needed for installing an ACG Filter preamp into a stomp box

[modlad69]

Hi gang,
Alan of ACG suggested I check here on TB to see if any FX box tech heads might know the answers to installing an onboard ACG filter EQ 02 premap for use as an outboard stomp box. Alan said some of his customers purchased his EQ 02 preamp and made it into a stomp box version.
There is one key question that would be helpful if someone could knowledgeably answer for me, that my amp repair tech asked me, who will be assembling the ACG filter into a stomp box casing with other parts:
"Using a dual pole, dual throw switch as a bypass,....will there be an audible noise when switching on and off?"
"Or, can you suggest a noiseless switching circuit?"
If anyone knows of a fx stomp box builder tech that you can refer to me, please do! Thanks much, gang!
Cheers!

 

[Crater]

Two things:
1) Don't wire the bypass switch to cut power to the preamp! Use a stereo input jack to connect the battery "-" to ground, like is done on effects pedals and in active basses. Preamps use very little current, your battery should last for months of normal use.
2) If you do get a pop when switching the preamp on or out of the circuit, you'll need to add pulldown resistor between the preamp's output and ground, a 1 megohm resistor is usually used - the value is high enough that it won't reduce the output or affect the tone in any way.

One more thing: you'll need a 3 pole, double throw footswitch if you want an LED indicator on your stompbox to let you know the preamp is activated. They're available by mail from any of the effect builders' supply houses.