phono stage still humming

Tubes Asylum

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So I now have a working phono stage. I rectified the heater supply on the signal tubes. The rectifier tube heater is still ac. I really think I have a grounding problem. It is a low level hum. I'm posting some modded schematics with notes on my grounding and changes. Maybe someone can help fix the hum. It is equal in both channels, low frequency and is evident at medium volume and higher. Just a note: my B+ is reading 294vdc when on and not connected to the phono or amp. It should be a little closer to 270v. Even with the problem it sounds like it will be better than what I'm using now. My wife says the tubes give the records a much more live sound than the NAD pp2. I sure hope we can get rid of the hum.

http://picasaweb.google.com/kkcinc.kevin/DropBox?authkey=Gv1 (Open in New Window)

Edits: 05/10/09

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Parts Connexion

Topic - phono stage still humming - kkcinc@verizon.net 20:02:29 05/10/09 (1)

RE: phono stage still humming - FenderLover 00:36:59 05/12/09 (0)

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