Anyone try undadjustable fixed bias?

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I am making a PP el84 amp out of an organ amplifier. The amp was originally a mono push pull parallel el84 amp with a 5u4 rectifier. I am just going to reuse the chassis sockets and power trans. This original amplifier PT has 2 bias taps one is CT and the other just a single voltage source.
So, I have been going thru various schematics and since the PT has a CT bias I would like to make an amp with fixed bias. The one scheme I like is the Scott 299 with a 6BL8 front end to PP el84 (7189). It seems like the circuit B+ would be about spot on with this power trans. I was just about ready to dive in when I came across a PP 6973 amp in the RCA tube manual. This amp uses fixed bias that is really fixed! I like this design because it is slightly simpler than the Scott 299 with the extra pots and wiring. So, I would use the Scott 299 schematic except with fixed fixed bias utilizing the ct bias supply with a FWBR and maybe a 5K pot so I can adjust the total amount of bias voltage. I also plan to put 10 ohm resistors on the el84 with a test point for each so I can at least determine the idle current for each el84 and select the 4 that are the closest. Anyway, I have not tried something like this before and wanted to know if anyone had suggestions or comments. thanks in advance, Dak

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Topic - Anyone try undadjustable fixed bias? - DAK 23:19:41 08/30/15 (7)

RE: Anyone try undadjustable fixed bias? - FenderLover 07:45:03 09/01/15 (0)

RE: Anyone try undadjustable fixed bias? - Triode_Kingdom 05:39:35 08/31/15 (5)

RE: Anyone try undadjustable fixed bias? - Paul Joppa 18:53:57 08/31/15 (0)

RE: Anyone try undadjustable fixed bias? - DAK 09:19:07 08/31/15 (3)

RE: Anyone try undadjustable fixed bias? - Triode_Kingdom 10:09:08 08/31/15 (2)

RE: Have you had a Rowe Ami amp? - DAK 19:51:42 08/31/15 (0)

And most were close to pure Class B operation (nt) - Chip647 14:28:00 08/31/15 (0)

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