Just melted 2 x EVM-12L in the same cab on their 1st gig !!!

[user 19640]

Just checked the Manual for the power amp and it doesn't say you shouldn't run either side independently. Else persons like my self with one speaker cab wouldn't be able to use them. I've been using the amp in the house since Nov last year.

They are two seperate amps, with seperate output transformers and only the heater circuits are active in standby so I don't understand how this would damage the power amp not connecting a load to the side I'm not using.

Please explain.

So, I have a 295 arriving soon that I bought: I am thinking about just running one side of the 295.

If I have understood this clear, there IS possible to have the unused channel on standby without speaker load ?
Would be a pain to blow such a good power amp...

 

[user 19640]

Bump!?

 

[japster]

Hi yes you can run 1 side and leave the other on standby, when on standby only the valve heaters are on so no current will flow thru the output transformer on the standby channel hence no damage could be done. In fact the only thing common to the both channels is the Power Transformer

Actually my original post about damage to speakers has now been found to be caused by an intermittent fault driving Channel A hard. When the output transformer on Channel A gets pushed hard it seems to short out after a while causing extreme speaker excursions and hence damage / overheating of the speaker coils.