In Reply to: the "COMPACT" ... posted by Sector-7G on April 9, 2004 at 20:30:48:
I picked up some 6528s based on the massive construction and specs but find linearity is poor. A triangle wave has a nice curve to both rising and falling slopes.I've read that with a more complicated circuit and several feedback loops this tube sounds great. This isn't a good tube for simple no feedback amps.
The compact works because of the sensativity of and ease of drive of the 6BQ5. Other tubes that might work well are the 7591 and 8417.
I'd be interested in seeing how ballanced the UL design would be. Having a signal on the G2 that is effected by the other output tube might make it more ballanced than pentode operation.
Of course not bypassing the cathode resistor or CCS would increase output Z.
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Follow Ups
- Re: the "COMPACT" ... - Scholl 07:31:11 04/10/04 (17)
- CCS and common cathode - Sector-7G 09:38:45 04/10/04 (16)
- interesting - Scholl 17:31:20 04/10/04 (15)
- Re: interesting - Paul Barker 01:47:40 04/12/04 (14)
- Re: interesting - Scholl 04:29:47 04/12/04 (13)
- Re: interesting - Henry Pasternack 19:41:35 04/12/04 (10)
- Re: interesting - Scholl 07:12:11 04/13/04 (9)
- Re: interesting - Henry Pasternack 11:20:59 04/13/04 (8)
- Re: interesting - MQracing 14:15:49 04/13/04 (7)
- Re: interesting - Henry Pasternack 16:11:56 04/13/04 (3)
- Re: interesting - MQracing 18:04:41 04/13/04 (2)
- Re: interesting - Henry Pasternack 20:37:06 04/13/04 (1)
- Re: interesting - arend-jan 00:42:18 04/14/04 (0)
- Paul, please correct me if I'm wrong... - Scholl 14:46:07 04/13/04 (2)
- Re: Paul, please correct me if I'm wrong... - MQracing 15:27:04 04/13/04 (1)
- Some preliminary tests - Scholl 08:01:58 04/15/04 (0)
- Re: interesting - Paul Barker 10:51:28 04/12/04 (0)
- Is this even a true diff amps? - Allen Wright 10:13:59 04/12/04 (0)