fx looper update & questions

[stirfoo]

I'm making a bit of progress on my fx looper. I got an Arduino Uno and started fiddling with it. I've got pretty much all of the logic working on a breadboard. I understand the logic. It's just moving combinations of 1's and 0's around. I'm not so confident when it comes to analog signal routing.

I've drawn up a couple of schematics for the loop and output select relays. The first is pretty big for clarity.





My question is about grounding. From what I've been reading I should keep the signal ground (PGND on the drawings) separate from the logic circuit ground. I think I have that okay on the drawings but what type of cable should I use? How should I physically route the signal wires? It's going to be a lot of short run connections. But the send/return lines might be kinda of long depending on the distance to the relay. I think I'll probably stack each send/return jack pair vertically.

Also on the output relay drawing, both amps will share the same ground. Is this going to cause problems?

Oh, while I'm at it. Where is a good place to get SPDT stomp switches? I'll need 16 of them. I've found a few on line. Seems like around $3 each.