20:20 problem : tubes, caps or ... ?

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gouzou

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hi all

My 20:20 ( old silver version ) is not amplifiyng but making raw distorsion : if I plug my active guitar in its inputs, all I get is a really distorted but really low volume sound . I may like heavy distorsion but I'd need a couple of watts from my power amp !!!

Long story short : I had bought it roughly twelve years ago as a nice complement to my beloved triaxis, but after a few months of moderate use ( few hours per week at low volume ) I had to abandon any possibility of playing loud and with a amp and cab, so the 20:20 sat on a shelf since then. It's sad, but it may have been turned on a handful of times in years ...

A few weeks ago I resurrected amp and cab ( a Cicognani box ), and tested the setup :
the cab works nicely ( tested OK with old Randall RRM power amp ), but the 20:20 behaves like described.

I was wandering :
Should I change tubes even though they have been used very little ?
( in this case, any advice on affordable and reliable non mesa-branded kit ? AP tube sets ? Eurotubes ? )
Should take it to the nearest Mesa technician ( 200km from here - Genova Italy ) for testing capacitors ?
Is there anythig else I should verify ?

thanks for any help :)
 
quick update : the fuse of course was first thing I checked, and it seems ok ...
I found a M.B. video about tube testing, I'll try to follow that even though I don't have spare tubes right now,
( I'll order a few soon but I was hoping to find some reliable tube-kit retailer on this side of the Atlantic )

any help on diagnosis would still be precious :)
 
A complete set of new JJ tubes has arrived and has been installed, but problem remains.
Any suggestion about how to check the board or the capacitors ?
Should I take it directly to some technician ?
 
Just to update the topic after taking the amp to a local skilled tech :
it turns out both the output transformers are dead :( :(
I'll be getting some drop-in replacements from Hammond, Mercury or BeyondEleven.
 
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