I have a Ceriatone DC 30 in that was brought to me after it failed during a stage break. At first inspection I noticed the rectifiers were lit and the V8 power tube closest to the rec tubes glowing like a Christmas tree. None of the other power or preamp tubes, which have been substituted, even show filament light even though all tubes have both ac and dc reading within the parameters. Tested the OT and it's fine. Can't get passed the lack of glow when filament voltage is present. Haven't tested the cathode to fixed bias switch but every test point checks out. The build is good except for a little sloppy filament wiring and the fact that there were two GZ34's in place instead of one or two 5V4's.
Any direction would be greatly appreciated.
Regards, Moejoe