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previous: Cliff Hey Brian.. Thanks for the info...a... -- 7/24/2000 3:40 AM View Thread

Re: filaments on D.C.

7/24/2000 4:24 AM
Re: filaments on D.C.
DC on the power tubes won't do anything for you. Your signal voltages are significantly large by then that the small magnetic interactions really aren't a big deal.  
You can run AC to the power tubes and DC to the preamp tubes on the same transformer tap. Just run the bridge rectifier off in parallel. -- I think-- I am not sure about having different references-- Say the CT of the winding is grounded, can you still run a bridge off of that winding and ground the negative of the bridge???? -- I dunno never done it.  
Does it really decrease noise? It depends on how crappy your wiring job is. A properly wired amp won't have any noticable noise from the filament hum. It may be worth it for you-- It's your call.  
The only stage that really needs careful heater routing is the first preamp stage. The small guitar signals are very suceptible to the magnetic coupling.  
Hum can also be grounding issues, if you have some in your amp. Play with the lead dress first.  

Bruce I agree with Brian... for the most ... -- 7/24/2000 4:51 AM