Is my Tube amp tube? (schematics enclosed) vht lead 20 and an el 84 bias question.

[timgman]

OK, after attempting to read the schematics I've found several IC chips.. as in the same chips we use in tube screamers...
are they only being used for the effects loop and reverb?

I see two in the "master section but perhaps they are for the effects loop?
I also was wonderin if my amp is cathode or fixed bias.
I know I'm asking annoying questions but I'm not an engineer and just want to know what to set the bias at should I change tubes.

[Enzo]

Your amp uses fixed bias, and it is adjustable. As to tubes, it is mostly a tube amp, with some solid state stages along the way. The only stage that gets bias adjusted in an amp is the powr amp stage, and it doesn;t matter in the slightest whether it was all tube up to that point or if parts of it were solid state. If you have power tubes, they need bias at proper level.

As to what to set it at, you appear to have current monitoring test points, so it would be up to the tubes you install and how hot you want them to run.