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ampeg v4-b biasing

7/7/2000 9:37 PM
danhei	ampeg v4-b biasing I just got his amp (ampeg v4-b) in an auction and had it taken into my local store to make sure it was set up correctly. They said the bias wasn't adjusted correctly and charged $40 to rebias the amp. It is, I believe, a cathode biased amp running four sovtek 7027's (they came with the amp). I've noticed that when I play two of the four tubes glow red on the edges of the plates (I think that's what they are called). Most of the plate is dark but along the seams where the two halves are joined together two of the four tubes glow red. Does this mean that these tubes are running too hot? Or is a little red nothing to be concerned about? I must say I wasn't very impressed with the music store...that's why I lurk on sites like this so I can learn how to do this stuff on my own! Thanks, Dan

7/7/2000 9:37 PM

danhei

ampeg v4-b biasing

I just got his amp (ampeg v4-b) in an auction and had it taken into my local store to make sure it was set up correctly. They said the bias wasn't adjusted correctly and charged $40 to rebias the amp. It is, I believe, a cathode biased amp running four sovtek 7027's (they came with the amp).
I've noticed that when I play two of the four tubes glow red on the edges of the plates (I think that's what they are called). Most of the plate is dark but along the seams where the two halves are joined together two of the four tubes glow red. Does this mean that these tubes are running too hot? Or is a little red nothing to be concerned about?
I must say I wasn't very impressed with the music store...that's why I lurk on sites like this so I can learn how to do this stuff on my own!
Thanks,
Dan

Replies:

Casey4s That amp is "Fixed Bias" and is not... -- 7/7/2000 10:48 PM
Ray Ivers Danhei,First off, I... -- 7/8/2000 8:48 PM