just a short one about the ohm-mismatch again

[petereanima]

we had a gig last week, 2 marshall 1960As as backline, and as we were short on time the local stage-tech plugged my Amp in. had a short talk with with him before, "from both 8ohm outs (=2x16) into each 16ohm input of the cab" - "yeah".

ending the gig, unplugging everything, i saw it: from both 4ohm-otputs (which should be used for 2x8Ohm) into the 4ohm-inputs of the cabs.

amp seems to work normally (at least at low volumes, i have to check on Thursday in the rehearsal room if there are sound-differences at "normal" volumes), ubt is there anything i can "check"? or is it "sounds o.k. = nothing happened, but your tubes may die sooner".

sorry for hasitating you with the over-talked topic, i know that "one step into each direction is o.k.", but as 2x4ohm = 2 ohm i dont feel all to well about it.

never trust "techs".

 

[Jakob]

If it still works, you're lucky. It doesn't always blow up the amp right away, but often. There are no delayed after effects in this matter.

I always check this myself, it's just too expensive to not take the three extra seconds.

 

[petereanima]

yeah, i usually do this myself only - but as he sounded very "knowing" with "i'll use both 8ohm, which are the 2x16, outs and plug into 2x16 ins of the cabs" - i thought it was all good. i've been proofed wrong.

 

[steppenwolf3080]

So basically you wired two 4 Ohm cabs in parallel, right? That gives you a 2 Ohm load and driven by a 4 Ohm output, right?
If so, don't worry. OT aren't THAT sensitive, especially not the ones Diezel uses. Loading the OT with a lower load then specified is a lot safer then loading it with a load that is higher or, worst case, no load at all.
Thats why some amp manufacturers use switching jacks on the outputs so that when there is no cabinet attached and somebody plays through it the OT is loaded short circuit and is still better then open circuit.

Don't worry, your amp is fine!
Best,
Stefan

 

[petereanima]

danke stefan!