In Reply to: RE: Broskie is correct on this one. posted by Stephen R on June 15, 2021 at 12:45:21:
I am very fond of a floating paraphase inverter that is adjustable. Rather than making the "perfect" inverter with a "perfect balanced output".
The advantages of the adjustable floating paraphase inverter is that you can adjust symetry with output tubes that have either more or less different amplification factors.
I measured this when I built an Audio Note clone that had a floating parapahese inverter followed by a6SN7 before driving the output tubes.
when the inverter was adjusted for "perfect symmetry" the end result with "perfect (within 1%) matched 6SN7 followed by "perfect matched" output tubes was more than twice as large as when I simply adjusted the inverter for best output.
When using less than perfect matched 6SN7's or output tubes the difference became larger although a hefty dosis of negative feedback attempts to correct this. But then IMD started to shoot up (the result of GNFB).
The moral of this post? Start viewing a design in its totality rather than splitting a design up and ending up with a worse result.
AM
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- RE: Broskie is correct on this one. - AmadeusMozart 14:57:00 06/16/21 (7)
- PI Balance - Triode_Kingdom 07:33:53 06/17/21 (5)
- RE: PI Balance - AmadeusMozart 16:03:07 06/17/21 (4)
- RE: PI Balance - Triode_Kingdom 07:47:56 06/18/21 (0)
- RE: PI Balance - PakProtector 06:02:41 06/18/21 (0)
- RE: PI Balance - AmadeusMozart 18:56:53 06/17/21 (1)
- Bias etc. - Triode_Kingdom 08:44:45 06/18/21 (0)
- RE: Broskie is correct on this one. - Stephen R 15:30:20 06/16/21 (0)