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Posted to rec.audio.tubes
Jon Yaeger
 
Posts: n/a
Default PP Amp driven SE

in article , TerryJ at
suptjudatcomcastdotnet wrote on 2/27/06 5:49 PM:

How about a LM317 connected for constant current in the cathode instead of
the choke?



A college friend who designs SS amps (his goal is to make them sound like
tubes!) used an LM317 as a constant current source in a SS phase splitter
and was disappointed with the results. It doesn't have a very good HF
response, and the current source's variable impedance interacted with the
phase splitter reference resistors, to the amp's detriment. The effect was
subtle, but he is currently in the process of redesigning the current source
and finding an alternative to the LM317.

Ergo, I'd pick a different device for a tube app.

I'll share with the group what he learns going forward, if anyone is
interested . . . .

Jon