meversesyou

Hi, im new to the forum and im not really techy so no technical jargon where possible. Cheers.

I have a JCM 2000 DSL50 head. I've got a problem which I need some guidance with.

After playing for a few minutes the volume drops off to nothing. The only way I get it back is by turning it off and coming back to it later.

The sound comes back but then it happens again after a few minutes.

I've had it years and have never changed the tubes? Does it sound like it could be this?

Any help is much appreciated?

Also, any suggestions for replacement tubes?

Cheers,


Ad

stryker59

first of all, welcome!!
it very well could be the tubes....change em all out, have it biased and i would think u would be good to go!

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Adwex

Sounds to me like something is overheating.

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spikei

does it do it on all channels? try swapping your pre amp valve around, turn off before hand.

Pete240885

I had a valvestate 8040 with a similar problem - the same but it would come back on after a while then drop out after another minute or so it turned out to be the filter capacitors on the power supply

Kjutte

Definitely not a fuse blowing, becuase they're not automats.
I bet there's something with the powersupply.

Maybe an overheating protection?
Check the voltage input, it may be lower than it should.

If the voltage is too low, the amps raise (ohm's law)
This will cause overheating!

Pete240885

Kjutte, the voltage being low will cause less current not more, ohms law states that
V = IR, in this case R is constant, and therefore V is proportional to I