spotted a jcm 800 1959 superlead in my local store. guy said I could take it away and try it out (no point trying it in the store, wouldn't get the volume past 0.5). got it home, plugged it in, let it warm up, switched it on and it sounded terrible. there was no crackle or buzz but whenever I tried to play something it was as though it was starved of power. hard to describe. I did notice the "on/off" switch light was a bit faint if that's got anything to do with it.....

im in the uk so amp was at 240v, 16ohms to match the 1960av cab

btw I plugged in my jcm 800 2204 straight afterwards and it worked fine...any ideas? valve trouble maybe?
It will either be the valves or the transformer, take it back to the store and get it repaired for free or get a refund.

Bit of a lesson here though, always try before you buy. Insist on cranking any amp in a store, if they dont let you just walk away.
You could try swapping tubes between the two amps (being british I can assume they both run EL34's, no?). A dull light can just be a dull light.
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