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Biasing signal tubes on a tube power amp/Quicksilver M120

Took possession of a new pair of Quicksilver M120 power amps with the KT150 tube upgrade a few weeks ago, am in the process of break in with about 70 hours so far. About 30 hours in I noticed that a 12AU7 tube had started to flare up when that amp was turned on so swapped that tube to the other amp and it followed the tube, I contacted Quicksilver and he told me that this is not a concern but to please switch that tube back to it's origional amp as the amp was biased for that specific tube, now my question is if I wanted to tube roll these 12AU7 or 12AT7 tubes am I out of luck and what happens when it is time to replace them as they wear out, are my tube rolling days over or are they just limited? What say you?
tooblue

Showing 5 responses by tooblue

tooblue OP
1,890 posts
 
@audioconnection , I am really liking the amps but still a bit confused as to the biasing of the smaller tubes, the power tubes are no problem biasing but I am not aware of the process to bias the smaller tubes.
tooblue OP
1,890 posts
 
@yogiboy , thank you , that is what I thought but did not know for sure.
tooblue OP
1,890 posts
 
@tubegroover , I am replacing a pair of VTL MB125s that are 21 years old, would have replaced with a like set but were out of my pay grade and took a chance on these, am very happy, just really hate break in time but so far have already showed themselves to be keepers.
tooblue OP
1,890 posts
 
@seikosha , @yogiboy , For clarity on my original post, I used the word bias when referring to the 12AU7 and 12AT7 tubes on my newly acquired Quicksilver M120 amps when the term balanced should have been used. 
tooblue OP
1,890 posts
 
@A_shah, yes I was informed by the builder that the signal tubes do need to be ballanced. 
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