RE: Check the power tubes next

Posted by djm1969 (A) on April 17, 2012 at 18:20:37

In Reply to: Check the power tubes next posted by Ralph on April 17, 2012 at 12:07:59:

It is a tube problem. I smoked couple of power tubes before being cautious enough with known good tubes from the other mono block and sound output has been restored. Both tube failures occurred to right rear left bank socket resulting in an immediate severe flash upon turning on full power. Violence of the flash seemed more then just an arc over. I have this bad habit of not discarding suspect 6as7 tubes that I have culled out over time for noise, bias and offset adjustment problems. i eventually start to reuse these as time goes on thinking there might be a good one or two in the bunch. I checked out your visual tube inspection link and might now have better luck culling tubes in the future. Time for some new ones!

Aside from this apparent tube issue, the capacitor that appears to be slightly swollen and leaking or corroded? I presume this is a source of sound quality degradation and will only get worse. Could this be causing a minor persistent hum? Would Atma-sphere have the correct replacement 1600uf power supply capacitor which I could purchase. Is it possible a bad 6sn7 could cause power tube instability and or failure? I do not have a tube tester so resort to trial and error when issues arise.
Dennis

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Follow Ups Full Thread

Topic - Atma-sphere m 60 mkII no sound - djm1969 15:41:38 04/16/12 (13)

RE: Atma-sphere m 60 mkII no sound - acres verde 08:53:44 04/20/12 (1)

RE: Atma-sphere m 60 mkII no sound - djm1969 22:16:19 04/20/12 (0)

RE: Atma-sphere m 60 mkII no sound - tyu 15:04:17 04/17/12 (0)

Did you check the fuses with a meter? - Ralph 18:39:54 04/16/12 (9)

RE: Did you check the fuses with a meter? - djm1969 06:56:10 04/17/12 (8)

Check the power tubes next - Ralph 12:07:59 04/17/12 (7)

RE: Check the power tubes next - djm1969 18:20:37 04/17/12 (6)

tube failure - Ralph 09:12:07 04/18/12 (4)

RE: tube failure - roscoeiii 12:28:33 04/18/12 (3)

The tubes can't arc during pre-conditiong as there is no B+ nt - Ralph 10:00:59 04/19/12 (1)

RE: The tubes can't arc during pre-conditiong as there is no B+ nt - roscoeiii 10:21:55 04/19/12 (0)

RE: tube failure - djm1969 16:57:41 04/18/12 (0)

RE: Check the power tubes next - tyu 05:32:38 04/18/12 (0)

Follow Ups

RE: Check the power tubes next - djm1969 18:20:37 04/17/12 (6)

tube failure - Ralph 09:12:07 04/18/12 (4)

RE: tube failure - roscoeiii 12:28:33 04/18/12 (3)

The tubes can't arc during pre-conditiong as there is no B+ nt - Ralph 10:00:59 04/19/12 (1)

RE: The tubes can't arc during pre-conditiong as there is no B+ nt - roscoeiii 10:21:55 04/19/12 (0)

RE: tube failure - djm1969 16:57:41 04/18/12 (0)

RE: Check the power tubes next - tyu 05:32:38 04/18/12 (0)

RE: Check the power tubes next

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