hi everyone
I got a small trouble with my bigblock that will hopefully be easily fixed but i wanted you opinion about it.
Last time i tried to play it , it went all fine for like 20 minutes and after that i didn t had any volume at all but a weird hum, a bit like the noise between two radio stations.
I checked all the cables, the bass and bladibla, it s all fine.
If i put the amp really loud (like 75 % gain and volume) i heard a tiny distorded bit of bass behind the hum and that s all.
Is this thing typical of dead preamp tubes? Like when they are cool it s fine but when they warm up, something happen.
i hope this is it... otherwise, what could it be ?
i opened the amp and checked the valves, they are still lighting up but they are not doing the "ringing" thing when i hit them gently with a pen...
i tried again today, and it does the same... 15 minutes and then humming
thx in advance.
gui