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BIAS TUBES VM220 ARC

I have the VM220 mono blocks by ARC. My problem is that on two pot #v1 and #v2 my millavolt meter reads -17.0 can not get anywhere near 65db's. Can someone please guide me in the right direction.
sjwholesale
brf
1,715 posts
 
I am not familiar with your amp, but what are your trying to measure? Most tube bias are in the mili-volt range. Are you trying to adjust the bias pot to read 65 mv? It sound like you multi-meter is on the wrong setting.
sjwholesale OP
9 posts
 
Hi, sorry for the typing error. Yes i am trying to adjust the pots to read 65 mili-volts. all the other pots i can adjust properly only #v1 and #v2 i get weird readings thanks
spinaker01
491 posts
 
Sounds like a bad or poorly matched tube-set. Try switching the offending pair to the other amp and retry. When all is working well, this should be an easy adjustment.
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