Hi. So I have a Boss GT-10 and a Carvin MTS 3200 head. The GT-10 has a mono amp channel switching output. The Carvin has a stereo input for it's switching which changes the channel and turns the reverb off and on. I would very much like to be able to switch the channels on the amp, and have no use for turning the reverb off and on. Running a mono cable from the GT-10 to the Carvin switches the reverb, same with a stereo cable. The amp works as it should with a regular two channel footswitch.

So I have a 1/4" stereo plug-to-two mono (L/R) 1/4" plugs adapter. Plugged into the Carvin I figured one of the two mono connectors would control either the tip or ring, and one of them would control reverb and the other channel switching. Both control the damn reverb. Crap.

Does anyone have any advice about how to make this work or know if I'm overlooking something here?

Thank you.
Last edited by hemiola at Jan 28, 2017,
So does the reverb switch on and off with that adapter, or is it always on?

To confirm the situation I'd plug a stereo cable into the amp and then use a paper clip to short the other end and determine which of the conductors shorting controls which amp function.
The ring connector is the part that controls the channel switching, the tip is for the reverb.

Below is the type of cable I tried.

When plugged into each female connector separately, both control the reverb. Everything I've tried, outside of my Boss FS-6 footswitch with a stereo cable, controls just the reverb. This thing is taunting me.

Can I take a stereo cable and just break the solder to the tip? Could I take a mono plug and wire it to just the ring of a stereo plug?
Attempt to clear this up a bit:
I need to make a cable that is TS (from switcher) to TRS (amp) with the TS soldered to the Ring of the TRS.

In my mind this would work perfectly.

Attempting to simulate this with the stereo TRS Male to 2 TS Female adapter has not afforded me expected results. Plugged into the Ring connector of the stereo adapter it controls the reverb. Plugged into the Tip connector of the stereo adapter it controls the reverb.

Am I missing something about how cables work? Is the ground wire doing something that I don't know?