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ARC 75 SE Bias Issues

Hi - I’ve been a happy ARC 75SE owner for over 5-years. I just moved to a new house and in the process my beloved 75SE stop working, here is what is happening: when adjusting the bias for the tubes, tuve #3 bias adjustment will not respond, the gauge is al the way to the left and won’t move. Is this a tuve issue or something else? Any other ARC owners had have the same issue? Thanks!
r_pig
imhififan's avatar
imhififan
2,180 posts
 
Not a reference 75SE owner. If no problem biasing V1 and V2,  my suggestion is swap V1 and V2 to V3 and V4, if the problem follow the tube, you have a bad tube, if bias adjustment cannot be done only on V3 position then it could be a bad potentiometer or bad tube socket connection...
rays19
9 posts
 
Does the needle respond for v4?
I had something similar happen on a REF75 shipped to me, it was just the needle that got stuck due to shipping shocks. There is a way to unstuck it, but I didn’t try.
jjss49's avatar
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jjss49
6,612 posts
 
does the amp fire up and play music with good even volume on both channels?  

agree with swapping tube positions and see if the problem follows the v3 power tube
r_pig OP
5 posts
 
Thanks everyone for the good insights. The needle does move when doing the bias for V4; so I think that I might have a bad tuve, or have a bad resistor on the bias circuit or both. Will do the tube swap to see if the issue follows the tuve--that would be an "easy" fix. Thanks again and will report back...
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