Digital guitar amp mod

[jjam47]

Hello,
I am new to this forum. I recently acquired a behringer V tone GMX212 guitar amp that has had the preamp section removed I’m assuming because it wasn’t working but the power amp and the speakers work fine. The master volume knob was removed along with the front panel so if I plug a pedal or some other type of preamp into the slave ins on the back panel I get full volume from the power section. I would like to convert this amp into sort of an frfr style cabinet but I would have to add a master volume somehow. Does anyone know if that is doable and how ? Thanks

 

[Nigel Goodwin]

Is there a common way of identifying which pin is which on those moduler ribbon connectors ? I’m having trouble with that. The ribbon cable has a red line on one of the wires...what does that tell me ? Thanks for all the help.

It tells you it has a red line on the wire - and that's really all.

It would be nice to think that it would be inserted with the red line connected to pin 1, but I wouldn't like to bet that it always is - check it with a multimeter on ohms.