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What OP tubes for DIY 6L6-type amplifier? pics

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I built this amplifier w/ circuit based loosely on the classic Harman Kardon Citation V amplifier. It is performing and sounding great. Currently I am using 6P3S-E tubes. They vary a bit when I set bias. B+ voltages are lower than anticipated - I have 375VDC on the plates, not the 410-415V I hoped for; but not really worrying about it. I suppose I am getting lower power because of the lower voltages? Probably fine since I don't want to strain the OP transformers - 6Kohm, rated at 35W from older Sherwood S8000 rcvr. (VERY good OPTs, judging by what I'm hearing.)
Anyway, getting to the point, what other new tubes would work well in this? New russian 7581s? TAD 6L6WGC? GL KT66s probably wouldn't perform at their best because of the lower voltages, I was thinking. Bias is around -33V. I can set each of the 4 OP tubes separately and run them at 46mA now. Maybe a bit too high?
(I dismantle old electronics equipment for parts and that's where the chassis came from, so I made it look sorta like a lab instrument).
Thanks for tube suggestions.
-Pete

Edits: 01/21/16

Follow Ups:

RE: What OP tubes for DIY 6L6-type amplifier? pics - REL54 13:50:39 01/21/16 (5)
Very nice/neat looking build. I like the partition between the power supply and the rest of the amp.

One question, what is the value of your first filter cap?

roN
- RE: What OP tubes for DIY 6L6-type amplifier? - PeterI 09:08:56 01/22/16 (1)
  Thanks. After full-wave diode rectification, 100uf (500V JJ cap) crossed with 5.5uf film cap (600V).
  
  303-0-303VAC CT > diodes > 100uf +5.5uf > 5H choke > 100uf B+ 375VDC > 210ohm > 370VDC screens, etc.
  - RE: What OP tubes for DIY 6L6-type amplifier? - REL54 15:05:37 01/26/16 (0)
    If you lower the value of the first cap your voltages may go up to where you want/expected them to be. If it is not too much trouble try swapping to a 40uf or even a 20 uf for the first cap.
    
    just a thought......
    
    roN
- The EH 6L6GC tubes are tough tubes - FenderLover 15:02:01 01/21/16 (2)
  Tone is as strong as the new TS 7581, IMHO. Been very reliable.
  
  Just my 2� worth! 8^)
  - RE: The EH 6L6GC tubes are tough tubes - DannyR 22:15:25 01/21/16 (1)
    I liked the tone of even the Sovtek 6l6wxt's.
    - RE: The EH 6L6GC tubes are tough tubes - Mechans 16:34:46 01/23/16 (0)
      Why not ask Jim McShane, he works on that kind of need routinely .

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