External Speaker Cab with Prosonic...

[brandish]

Hi, new to the board but have a question concerning running an extension cab on my Prosonic.

My buddy has a Marshall 1960 cab and I thought i'd plug it in and see how it sounded. On the back of those cabs you have 2 jacks and a switch. The jack on the left would be for running the cab Mono with a 4ohm load. The jack on the right is for running it Mono with a 16ohm load. The switch changes all of that to stereo left and right.

So, unplugged my speaker cable into the 16ohm jack Mono and connected it to the external speaker jack on the back. You could barely hear anything. What am I missing? I know the cable was a good one because I was playing through his head using it early as well as after attempting this.

Thanks

[Gutmann]

You are using the 2* 10 combo or the head? If it's the combo(as I assume), try this: unplug the combospeakers and run the amp direct into the 412, to check if youre ext. speaker jack is the problem. Those jacks are switching jacks and by the heat the amp produces, the they go bad - maybe plug the cable in and out a few times.

So far, everything else is right, ext. sp.jack into the 16 ohm input on the 412 set to mono - can't see a mistake here.

Great amp, but it doesn't fit with the 1960. But it works very nice with a Greenback/V30Mix - if you ever think of an extension cab, get a 212 with those: