Laney tube amp problem VC 30

[mike 54]

I just recieved a Laney VC 30 210 30 watt combo amp. It has a clean channel that works fine. It has a Drive channel that is barely audible with drive and drive volume turned all the way up. I changed all 3 12ax7s and nothing changed. Do I need to change all 4 EL84's or do I look elsewhere? As you can tell I'm new to this so any help would be welcome.
Thanks,
Mike

[Enzo]

If the clean channel works OK, then the power tubes are good. They have no idea which channel is on.

If the tubes were OK, then start looking for voltages. Got reasonable B+ on all the 12AX7 plates? Got some reasonable cathode voltage on each? if those are OK, then trace the signal stage by stage with a scope or an AC voltmeter. Alternatively, inject a signal stage by stage to see at what point the injected signal does not pass on through the amp. Just touching a circuit point with a small screwdriver or something to make a hum signal is often good enough to do go/no go tests.

[mike 54]

Laney VC 30 Schematic needed!

Thanks ENZO! Does anyone know where I can get a schematic for a VC 30 210 Laney? Thanks, Mike