What OT for 4- 6V6 Marshally build?

[Deric]

I agree with everything said here so far. My gut instinct would be somewhere between 3.2k and 4.2k.....

...but, and to me it's a BIG BUT (I just said "big but" )....

You built AND posted clips of THE amp you want to emulate. What trafos did it use? I'd start there.

[Roe]

Terribly easy choice here, a Marshall 50w Drake or clone.

784-139

TM

yes, -139. You could just use a pair of el34s if you want w/o changing sockets or anything (except for a rebias). I'd shoot for a 415v plate voltage 470R screen resistors. try finding a 1202-118 PT with dual or trial secondaries perhaps (marstran or classictone).

[gingertube]

I built a 4 x 6V6 for a friend. The Output Tranny I used was a spare 50W Marshall I had on the shelf - that is Raa = 3K4, originally intended for a pair of EL34. I got 27 Watts out of it just below clipping. B+ was 345V with each 6V6 idling at 24mA.
This was a London Power "Standard" from TUT5. Full Power Scaling, Cathode/Fixed bias switching, Pentode/triode Switching, SAG Control etc.
I used a Hammond 370FX Power Tranny.

If starting from scratch with no tranny on the shelf I might go for a Hammond 1645 which is a 30W 5K Raa.

Cheers,
Ian