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How best to place tubes in an ARC VT-130SE

I have two matched quartets of 6550EH Platinums that I am going to put in my amp. One quartet's tubes measure lp: 39 and GM of 5,700, 45 ma. Every tube in the other quartet measures lp: 36, GM of 5,400, 44 ma. There are tube positions of V4-V7 on left and V14-V17 on the right. The quartets are perfectly matched. I want to achieve a "match" between the sides. Anyone with any experience as to where I should place these to have both sides "balanced" with each other? I understand it is identical to the VT-130 as well. Thanks.
madgalatea
jea48
4,788 posts
 

http://www.audioresearch.com/ContentsFiles/VT130_BiasAdjust.pdf


Install one matched set on the left channel side and the other matched set on the right channel side.

(V4 - V7 Left Channel)  (V14 - V17 Right channel)


http://www.audioresearch.com/ContentsFiles/VT130SESchPL.pdf

madgalatea's avatar
madgalatea OP
26 posts
 
Thank you. The previous owner of the amp advised me to put two of each quartet on each side of the amp, thus "averaging" them on each side, and as well "averaging" each side to the other. Or something like that. The Ruby 6550's in it now seem fine, but I thought I would put new ones in an abundance of caution.
jea48
4,788 posts
 

The previous owner of the amp advised me to put two of each quartet on each side of the amp, thus "averaging" them on each side, and as well "averaging" each side to the other.
Have you ever install new power tubes in an amp that needs to be manually biased? 
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