Re: Cruelty to a 12AU7 ?

"With CR coupling of 6550 grids from the CF cathode, you should have 6
caps and six pots and six
bias R with 10 ohm Ia sensing R between each 6550 cathode and 0V.
if there is only one bias voltage applied to all 6 x 6550, some will be
running hot
and others running cool, and the hot ones fail first.

I've never had any success telling the yanks how to build their amps.

I get a lot of work rewiring their junk."<<

The original SVT used a different driver tube that was well specified and
6146 outputs. Bill Wyman got 10+ years out of the original set.

The current production is a St. Louis Music/Gene Kornblum bodge. Done as
cheaply as possible.

We can't even straighten them out,and it's unlikely you'll succeed
either. But you are right, a lot of crap is built here-along with
everywhere else.

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