In Reply to: What is the typical source of hum in a Kit 1? posted by 12ax7 on June 3, 2004 at 05:30:36:
2 things: Are you using an indirectly-heated rectifier (ie GZ37/CV378)?
If not, have you checked your power supply caps?
Sometimes the initial voltage surge (with a directly-heated rectifier like a 5U4)is greater than the limit of the caps. They don't fail outright, but a residual 60hz hum results. (my reference on this point currently escapes me)
Regardless of the cause, don't automatically assume that more efficient speakers will accentuate this hum. Sometimes the audibility has more to do with the tonal characteristics of the speaker.
Mark
Edits: 09/03/20
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Follow Ups
- hum in a Kit 1? - markmac 10:21:46 06/08/04 (5)
- Markmac the rectifier is a GZ37 - 12ax7 14:23:01 06/08/04 (4)
- Re: Markmac the rectifier is a GZ37 - try a 5U4G - fred76 03:34:34 06/09/04 (2)
- Re: Markmac the rectifier is a GZ37 - try a 5U4G - 12ax7 05:28:07 06/09/04 (1)
- Re: Markmac the rectifier is a GZ37 - try a 5U4G - fred76 08:59:39 06/09/04 (1)
- Re: Markmac the rectifier is a GZ37 - 12ax7 14:27:10 06/08/04 (1)