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previous: Chris Harden I've only just found this post, bec... -- 6/4/2000 10:44 PM View Thread

Re: Building a 'clean' PI

6/5/2000 2:59 AM
Ray Ivers
Re: Building a 'clean' PI
I would call that circuit a 'self-balancing paraphase' inverter, but it may well have the name 'see-saw', as well. I've always thought that circuit would be more popular in guitar amps, for the very reason it isn't in hi-fi amps (potential for more distortion). It's a hi-gain, hi-output-voltage design, and allows easy adjustment of AC output stage balance. At 550 volts B+, a 12AT7 should be pulling almost 380 volts peak-to-peak AC with 56K plate loads, 220K output tube grid resistors, and a 470 ohm common cathode resistance - headroom city! Current draw is still a little low at 8.6 mA, but it's better than it was.  

Bruce Ray, have you tried running that si... -- 6/5/2000 7:50 AM
Chris Harden Ray,Thanks for givi... -- 6/5/2000 9:55 AM