More on dealing with the SansAmp squeal

[Samuel]

I've read the threads in the archive - and it seems like the sqeual is entirely correlated with the physical reality of using a stomp switch. So I guess I'm looking for alternative switching arrangements, and wanted to poll the population here and get some ideas about the best way to accomplish this.

Obviously, the main criteria is to get the effect input and effect output wires at least a couple inches away from one another.

An obvious route would seem to be the ultra-simple SPDT-on-the-output-jack method, but I understand this raises some impedance concerns. Would a basic buffer on this signal path be sufficient to undo the tone suckage? Are there going to be "pop" problems moving away from True Bypass?

Is electronic switching a better way to deal with this? I'm concerned much more with stopping this squeal than getting absolute 100% unaffected bypass. If there are minor differences in tone when bypassed I can deal with that.

[cd]

Yup, FET switching is your best bet.  Small, cheap, easy to wire the in/outs away from each other with the control even farther away (install a jack and use a regular amp footswitch with a long cord.)

[Samuel]

Any good links for articles / schematics on FET switching? Haven't looked terribly hard, but if you know something off the top of your head that would be great...

[Samuel]

I'm going to bump this with another question. Do I need to bother with FET switching for my purposes? I'm perfectly content to use half my stompswitch to switch between the two outputs (the buffer out and the effect out).

Owing to an earlier thread on the subject, can I just wire from the output of the first opamp through an appropriate output cap, as it was stated on an earlier thread that Tech21 used the first opamp stage as a buffer, and took the "bypassed" output from there in their version of the pedal...

So I guess what I'm guessing will work is:


Input hard wired to pcb in
-
Wire from output of first opamp -> output cap -> to throw 1 of spdt
effect output -> to throw 2 of spdt
output jack wired to spdt pole

Will this solve any lurking impedance issues?

[cd]

Whoops, I forgot you were doing this with a Sansamp.  Yeah, I would just use the SPDT switching.  Then you get a nice low Z buffered out in bypass mode.  The input Z of the effect is high enough so that it won't load down your signal much (if at all) so you could even wire one throw to the input jack.

[Samuel]

Good to know! Thanks alot cd!