6e5p gm70 with 6d22s?

[enzoastro]

Hi all

sorry if this is a stupid question, but i've always been of the understanding that capacitor value after a valve rectifier was limited, ie 40~60uf

Having just read a load of posts conserning 6d22s's it seems i could use much larger values after a choke in a pi filter, is this correct? Duncan ps simulator doesn't flash up any warnings which seems promising what are peoples experiences with the damper tubes and bass speed ?

The amplifier as it stands has 6e5p mu follower running from 700v @ 200v 23ma the load resisters drop 300v and so produce quite some heat.

ps is 400 0 400 bridge rectifier using series 4007 to a 10H 350ma choke then 4 x 1500uf 250v in series producing 725v.

GM70 are biased with 470r for -50v ish at 675v

i'm planning on fitting a small value pio cap before the choke to give me ~900v and use fixed bias on the GM70s. as 6d22s@s are quite cheap and seem to have some favorable reviews sonicly i was considering them, but was put off by having to have small value capacitors which from my modest experience fiddling with old quad 11's gives bloated bass.

ultimatly i hope to have a great sounding amp, roughly 10-20watts and keeping it domesticly acceptable ( not cool i know!) so that means keeping it in or on its 300 x 110 x 600mm chassis and that demands limiting hot components within the chassis which aint easy with gm70's i'm finding out!

enzo