Multiple amps again.

Unless you have some really modern amp with only one input jack, running a cord from input 2 of one amp to input 1 of the next worked for Eric, Jimi, and a host of others back in the day.

 

Do you mean you still want to connect both amps to one cab, but just have them on at the same time?

If so - you can't, period.

You cannot connect the output sections of two amps together like that without frying something... one or both amps.

The only way around it is if the cab has more than one speaker, and each speaker will take the power output of each amp, you could rewire the cab for stereo - effectively two separate cabs in the same box.


If you do mean you want to just connect the inputs of both amps (each with a separate cab), you can do that with a Y lead, yes.

 

Opps, missed the bit about one cab in my original reply.

Doesn't someone make some sort of switching system that lets you run the other head into a dummy load while you're playing the first one? The idea had occured to me at various times but the reality of making something that would handle the power, switch fast enough, be reliable, and not send huge transients through an unterminated amp while switching on the fly, always sounded scary to me. Does this thing really work?

This sounds more like an attempt to get more volume by ganging up on the speaker cabinet with two amps. Something similar to bridging a stereo amp. I suppose if you had two exact duplicate amps, you could rig up some sort of bridge arrangement, but keeping two tube amps operating consistently would be pretty tough.

Cheapest way to more volume, more efficient speakers. There are plenty of choices out there right now at 99db/1W/1M and higher.

 

Not really, you can still do this. But run each OT out to it's own speaker load. There are stereo amps after all!