I'm building a simple patch bay for my pedal board to make it easier to set up at gigs. I bought the wrong jack sockets though, I got these


Instead of these:


Can I still use them? How would I wire them? I'm basically building this:

I can probably exchange them but it'll cost in petrol, but if I'll get better quality with mono the I will...

Those will be fine. If you are going to be using mono cable you can use either of the ring or sleeve contacts and they will function fine.
Certainly can. Most patchbays in fact use TRS jacks so that they can be used with balanced signals.

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