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previous: Stephen Conner Hi David,In amps li... -- 11/8/1999 2:16 PM	View Thread

Re: Advanced feedback loop questions..

11/8/1999 4:43 PM
anonymous	Re: Advanced feedback loop questions.. ok.. so negative current feedback is used to raise impedance on solid states.. it wouldnt be of any real use in tube amps because impedance is already high.. Is a 16ohm impedance more bass/mid heavy than an 8 ohm impedance.. or is there only a slight difference in the sound? I also tried the 3 cap LFO trick on the actual feedback loop instead of around a single gain stage and no oscillation -- at least none I hear.. what gives? I got lots of lowend motorboating when I used put it in parallel with one of the preamp stages.. I also would like to know how to convert negative feedback to positive feedback.. is it a change in polarity or just phase? - how would I attempt doing that - I remember someone posting about having wires backwards on a output tranny somewhere... oh.. is the "Art of Electronics" applied directly to tube amps or is it a general book on negative fb and audio?

11/8/1999 4:43 PM

anonymous

Re: Advanced feedback loop questions..

ok.. so negative current feedback is used
to raise impedance on solid states.. it
wouldnt be of any real use in tube amps
because impedance is already high.. Is
a 16ohm impedance more bass/mid heavy than
an 8 ohm impedance.. or is there only a
slight difference in the sound? I also
tried the 3 cap LFO trick on the actual
feedback loop instead of around a single
gain stage and no oscillation -- at least
none I hear.. what gives? I got lots of
lowend motorboating when I used put it in
parallel with one of the preamp stages..
I also would like to know how to convert
negative feedback to positive feedback..
is it a change in polarity or just
phase? - how would I attempt doing that -
I remember someone posting about having
wires backwards on a output tranny
somewhere...

oh.. is the "Art of Electronics" applied
directly to tube amps or is it a general
book on negative fb and audio?

Replies:

Don Symes It _is_ a reversal of polarity to s... -- 11/8/1999 7:05 PM
Stephen Conner Hi,The difference i... -- 11/8/1999 7:37 PM