Adding Speaker Output to a Combo Amp

I have a solid state 1X12 combo that I would like to hook up to my 4X12 cab. Can I hook up an outbput jack between the combo's speaker and its wires and still have the amp work properly when disconected?
Any help is appreciated and thanks in advance


You can, but how about impedance matching? IF the onboard speaker is 8 ohm, for example, better use a 8 ohm 4x12 and make sure the output jack you add switches off the onboard speaker.

Kyle B

Silver Supporting Member
Your cab can be higher impedance than the stock speaker, but do not go lower.

You will want a 'switching' jack to turn off the combo speaker when the cab is plugged in.

Make sure you electrically isolate the new jack from the chassis. It might be OK to have it connected, but it might not.

This is a simple mod, won't cost you more than $5 if you DYI


I've done this to one of my combo amps. I just inserted a switching jack between the amp and the speaker. Solder the leads from the speaker to the side of the jack with the contacts. Solder the leads from the amp to the other side of the jack. When you plug in a speaker cable the contacts will be broken and the amp output will be rerouted to the cable.
Get a mono switching jack and plate like this and add it the the back the combo amp.