#1
I recently obtained this awesome amp called the Genz Benz Black Pearl 30. It was working great until I moved it into another room today and fired it up. No sound! If I max everything, I could get a tiny bit of fuzz aroud the volume level of a mosquito flying around through my Emperor 2x12 cab. Once in a blue moon when I was adjusting the tone controls I could hear it try to get going, but not even long enough for a note to ring out.

I checked all of the obvious stuff- all cables, cabs, even power supplies.

I then had to remove the amp from the chassis to get in at the tubes. I tested for microphonics... all good. Everything appeared to be firing up normally and since I had various 12AX7's on hand, I did some testing by swapping out all of the 5 preamp tubes. Power section appears to be fine. Rectifier tube appears to be running a little hot (maybe they just run hotter). This amp came with mainly EH tubes, but the rectifier tube is some Sovtek. I don't prefer Sovteks, not when JJ's are available.

While I was swapping tubes and eyeballing stuff, I used a little contact cleaner on the tube sockets.

I noticed my reverb tank was a little janged up with a spring hanging out of it. Not sure if this is the cause of the issue.

My intuition is telling me rectifier tube.

What do you guys think?
#2
Buy one and try it, they aren't expensive. If that isn't the fault then you will have a spare.
Gilchrist custom
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Atomic Amplifire
Marshall 1960A
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Cathbard Amplification
My band
#3
Any other thoughts? I don't know what can go wrong in relation to a spring hanging out of my reverb tank. Can it can electrical problem if the spring touches anything it shouldnt?

I ordered a rectifier tube. Hope it works. I am eager to get this amp going again! It has the sweetest palette for cleans I've ever come across. My Rectoverb has nothing on it.
Last edited by cGoEcYk at Jan 2, 2014,
#4
Check the fuses. The reverb tank shouldn't cause that particular issue. I'd get a new set of power tubes as well, they would be a suspect and as mentioned above you should have spares for all that stuff (recto, power tube set, fuses, a few pre tubes) anyway. It makes these issues a lot easier to diagnose, and you'll need them eventually even if it's not the issue this time around.