Hey all,

I am not experienced with electronics at all, but wanted to try a mod out on my Marshall MG15FX combo. I recently bought a Marshall 4x12 cab and wanted to see what the combo sounds like through the new cab. However, the Marshall didn't have a speaker output, so being the adventurous person that I am, I decided to try and make a simple one

I simply just bought a jack and disconnected the output wires and attached them to the jack. Is this safe?

Image of the jack:

Image of front end of amp:

Image of the inside:

Close-up of the jack inside:

Thanks guys.
As long as the cab's impedance matches or is greater. I think the mg speaker is 8 ohm so the cab will need to be 8 or 16 ohm. As long as it is it should work fine. I modded an old line 6 spider combo to be an extension cab using a jack like that and it worked fine.
Last edited by Liaztraht at Nov 13, 2016,