UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

Diabolical Artificer · 11th Oct 2019, 7:18 am

"Not for the 6L6GC specified in the design as these are rated at a plate dissipation of 30W so a pair in class AB push pull is well within the rated power." AFAIK you don't double power OP, EG it's not 2 x 30w as only one valve is working in the class B part of cls AB PP at a time, therefore two 6L6's biased at 30w each will give you 30w OP.

Re tremelo circuits I'm working on a WEM amp, see attached schematic. The amp has separate mic IP's which give a clean hum free OP, but using the tremelo IP's results in quite bad hum, this is refardless of the tremelo being on/off. I've been over the wiring/layout and checked components but am convinced the hum is down to the design. What's your circuit like as regards noise? Are tremelo circuits noisey on the whole?

Andy.

11th Oct 2019, 7:18 am	#36
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,670	Re: Fender amp copy "Not for the 6L6GC specified in the design as these are rated at a plate dissipation of 30W so a pair in class AB push pull is well within the rated power." AFAIK you don't double power OP, EG it's not 2 x 30w as only one valve is working in the class B part of cls AB PP at a time, therefore two 6L6's biased at 30w each will give you 30w OP. Re tremelo circuits I'm working on a WEM amp, see attached schematic. The amp has separate mic IP's which give a clean hum free OP, but using the tremelo IP's results in quite bad hum, this is refardless of the tremelo being on/off. I've been over the wiring/layout and checked components but am convinced the hum is down to the design. What's your circuit like as regards noise? Are tremelo circuits noisey on the whole? Andy. __________________ Curiosity hasn't killed this cat...so far.