Old topic with lots of info available on this forum, but I am still stuck.. I'm also very new to any form of electronics and took this on with the hope of learning something new and also having a beautiful looking and sounding amp.
I'm building a 6sn7 pre amp with vintage parmeko transformers and choke (supplied as "kit" by a local tube amp builder),and have been battling to get rid of hum (even with the suppliers assistance)
It seems like 50Hz, and is not affected by the volume pots. What I have done so far: I tried moving the transformers, choke and rectifier tube far away, changed tubes, changed rectifier tube, added DC supply to the heaters (from tentlabs, but actually made for directly heated tubes) I've added shieding over tubes, between transformers and everything else. Any ideas?
I'm building a 6sn7 pre amp with vintage parmeko transformers and choke (supplied as "kit" by a local tube amp builder),and have been battling to get rid of hum (even with the suppliers assistance)
It seems like 50Hz, and is not affected by the volume pots. What I have done so far: I tried moving the transformers, choke and rectifier tube far away, changed tubes, changed rectifier tube, added DC supply to the heaters (from tentlabs, but actually made for directly heated tubes) I've added shieding over tubes, between transformers and everything else. Any ideas?
Welcome
I am not a tube guy but I bet the folks over here can help
https://www.diyaudio.com/forums/tubes-valves
I am not a tube guy but I bet the folks over here can help
https://www.diyaudio.com/forums/tubes-valves
Welcome to the Audio OCD club. On the subject of hum, are the input and output connectors isolated from the chassis? You will likely get a lot of good help here. HeyBill
And here's some pics. The loose wires are the Virtual centre taps that I disconnected when fitting the DC supplies. I've tried various ground connection options since then without any change..
Welcome to the forum. For best results, go ahead and start a new thread over in the Tubes/Valves section.