In Reply to: WE 300b and Cary 805AE posted by Gerado on November 22, 2007 at 03:38:13:
Gerado, hi. By definition the 845 has a thoriated tungsten heater/cathode. It dissipates max 100 Watts. Observe how many "845" of current manufacture do not meet these specifications. I would probably rank OS RCA and United 845 in best of type category. Regarding RCA & United 845 - be prepared for sticker shock. At some point I suggest trying the JJ Electronics 300B versus the WE. The 805 has a power supply that is sub-optimal: silicon diodes, no choke, and electrolytic caps (the ubiquitous 1200uF 450V). I don't think there is room on or in the chassis for anything else. Try this test. Take a #2 wooden pencil and lightly tap on the glass of the 300B and the 845 while the amp is operating. Note microphonics. The 805 must be carefully isolated to lessen "spring reverb" effects. Rolling tubes may give you the feeling of optimizing the amp but cannot overcome circuit limitations. The 300B is interstage coupled to the 845. Is the interstage optimal? Was the horrible mechanical hum you describe cured by transformer replacement?
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Follow Ups
- RE: WE 300b and Cary 805AE - elektron 11/22/0707:31:19 11/22/07 (9)
- RE: WE 300b and Cary 805AE - Gerado 14:31:20 11/22/07 (8)
- RE: WE 300b and Cary 805AE - elektron 16:48:04 11/22/07 (1)
- Don't forget to add a choke in the PSU ... - Naz 21:45:36 11/22/07 (0)
- RE: WE 300b and Cary 805AE - jim94025 15:45:55 11/22/07 (5)
- RE: WE 300b and Cary 805AE - Gerado 21:43:31 11/22/07 (4)
- The huge peak currents with this type of PSU is half the problem ... - Naz 21:52:22 11/22/07 (3)
- Amen to the chokes - elektron 22:01:56 11/22/07 (0)
- RE: The huge peak currents with this type of PSU is half the problem ... - Gerado 21:57:22 11/22/07 (1)
- Outboard PSU is OK but ... - Naz 03:55:17 11/24/07 (0)