Got great results with 811A parafeed
Here's the schematic:
http://world.std.com/~doyle/811Afunproject.pdf
This design is similar to Bob Danielak's 826 amp. It is very cheap to build too
and you can use simple Series Fed output transformers (Edcor, Big Hammonds).
In my case, I turned my Hammond 1628SE into a big plate load choke and used
a Nickle cored parafeed transformer. A bunch of guys listened to this (Karlson horns, Fostex, other stuff) and really loved this - more so than the 845.
This is good for 8-9W. Strong watts too, with tight bass and surreal clarity with the high. The dynamics sparkle.
I'd try it first with AC filaments on the 811A and a humbucking pot. If and only if
hum is too much, then attempt a DC supply for the 811A filaments. A DC supply
for the 811 will be expensive and complex. Rectifying 4A of current with no RF artifacts is going to be tough. You'd need a common mode choke for sure.
-- Jim
Here's the schematic:
http://world.std.com/~doyle/811Afunproject.pdf
This design is similar to Bob Danielak's 826 amp. It is very cheap to build too
and you can use simple Series Fed output transformers (Edcor, Big Hammonds).
In my case, I turned my Hammond 1628SE into a big plate load choke and used
a Nickle cored parafeed transformer. A bunch of guys listened to this (Karlson horns, Fostex, other stuff) and really loved this - more so than the 845.
This is good for 8-9W. Strong watts too, with tight bass and surreal clarity with the high. The dynamics sparkle.
I'd try it first with AC filaments on the 811A and a humbucking pot. If and only if
hum is too much, then attempt a DC supply for the 811A filaments. A DC supply
for the 811 will be expensive and complex. Rectifying 4A of current with no RF artifacts is going to be tough. You'd need a common mode choke for sure.
-- Jim
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