Golden Tube Audio SE-40 bias problem


I own a Golden Tube SEP-1 and a SE-40. I can properly bias tubes V3 and V6, but the others stay in the vicinity of 100-150mv. I've tried tube swapping and new tubes. Neither action makes any difference. Does anyone know what the problem might be?
jjsaudio
This is a dumb question, but is the SE40 new to you and is this the first time you've tried to set the bias?

I had to ask because the diagram of the molex bias connector in the owners manual is confusing. Looking at the diagram, you can't tell if it depicts the plug or the socket. Your measurements tell me you chose the wrong wire as the common ground.

In any case....The Red Wire on the Male molex connector (#4 marked on the plastic) is the common negative ground for all tubes. The negative (black) test lead from your meter goes on that wire. The other 3 represent each tube on that channel.

If you have 3 meters it makes biasing the SE40 much easier because as you raise one, the other drops and vise versa.

Also-minimum bias is when each pot is turned fully clockwise. Start there and increase gradually. Unless you have 6 meters and 2 molex plugs you'll have to go back and forth till you get it right.

Good luck.
Rich
A service manual which fully explains how to bias the SE-40 with diagrams and pictures is available on the Golden Tube forum at Yahoo groups.

It's slightly tricky given it's a common cathode amp the bias of one tube affect the others. Biasing must be done in a specific sequence.

http://groups.yahoo.com/neo/groups/golden_tube/

-David
Try the Golden tube users group on yahoo groups.
A plethora of knowledge base and
Very helpful people there.