Hello I have a stereo amplifier that came out of a thomas organ. This amp has a 12ax7 6cg7 and a 4 6973 tubes. I am converting this amp to run the 6cz5 because the 6973 is getting tuff to find. What I have done so far is 1 dropping resistor of 560 ohms in the power supply which has helped drop the voltages from 440 to around 380. This amp has fixed bias and from what I have read the 6cz5 cannot see more than 100k at the grid #1 and when I look at pins #3 and 6# there are no resistors that go to ground so my question is should I add them or leave it alone ?
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Topic - Thomas stereo organ amplifier 6973 to 6cz5 conversion - joshie 19:21:11 01/14/22 (22)
- RE: Thomas stereo organ amplifier 6973 to 6cz5 conversion - Jim McShane 18:51:17 01/17/22 (0)
- RE: Thomas stereo organ amplifier 6973 to 6cz5 conversion - Palustris 07:49:33 01/15/22 (1)
- RE: Thomas stereo organ amplifier 6973 to 6cz5 conversion - joshie 14:10:58 01/15/22 (0)
- RE: Thomas stereo organ amplifier 6973 to 6cz5 conversion - Triode_Kingdom 21:16:43 01/14/22 (18)
- RE: Thomas stereo organ amplifier 6973 to 6cz5 conversion - joshie 04:33:21 01/15/22 (17)
- can you post a schematic? - Tre' 16:43:17 01/15/22 (5)
- This might be close. - Tre' 06:32:53 01/16/22 (4)
- RE: This might be close. - joshie 10:12:32 01/16/22 (3)
- RE: This might be close. - Tom Bavis 11:08:47 01/16/22 (2)
- RE: This might be close. - joshie 12:12:50 01/16/22 (1)
- RE: This might be close. - joshie 13:33:09 01/16/22 (0)
- RE: Thomas stereo organ amplifier 6973 to 6cz5 conversion - Triode_Kingdom 16:14:33 01/15/22 (9)
- RE: Thomas stereo organ amplifier 6973 to 6cz5 conversion - Paul Barker 03:34:33 01/16/22 (8)
- RE: Thomas stereo organ amplifier 6973 to 6cz5 conversion - Tre' 06:29:48 01/16/22 (7)
- Agree - "grid resistor" - but then again... - Triode_Kingdom 11:28:23 01/16/22 (6)
- RE: Agree - "grid resistor" - but then again... - Paul Barker 23:14:30 01/16/22 (5)
- That's called "dumbing down" - Triode_Kingdom 10:11:12 01/18/22 (4)
- RE: That's called "dumbing down" - joshie 07:54:55 01/22/22 (3)
- RE: That's called "dumbing down" - joshie 08:24:03 01/22/22 (2)
- RE: That's called "dumbing down" - Tre' 16:35:27 01/22/22 (1)
- RE: That's called "dumbing down" - joshie 16:35:35 01/29/22 (0)
- RE: Thomas stereo organ amplifier 6973 to 6cz5 conversion - Tom Bavis 14:24:05 01/15/22 (0)