do they only work with marshall amps?
cause when i put one into my fender fm65dsp amp (on the clean channel of course) it wouldnt change it to the second channel??
you just answered your own question...
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Quote by Nirvanafanjonny
you just answered your own question...

well sort of, but thats only with my amp..
Nope, i have a marshall one going into my engl fireball 60w head and it still switches channels fine.
It all depends on how the relay and jack are wired, but generally footswitches are interchangeable.

I used a Rectifier pedal for my Valveking ages ago.
Everyone is entitled to an opinion.

Feel free to express yours so I can make an informed judgement about how stupid you are.
I have the single marshall footswitch (without LED), it works fine through my Laney GH100L.
You might need the second channel active first for the footswitch to switch between them. I think this happens on some amps. So put on the second channel, then plug in the footswitch and see if it works.