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Can't get enough power for proper Bias

7/10/2000 6:50 PM
Tom	Can't get enough power for proper Bias I own an older Marshall JCM900 Head in covered in the old White Tolex. My problem is that I can't seem to get a good tone out of it. It seems to be tired and only gives a weak tone. I had the amp re-tubed and re-biased, and that helped a little but when I went to re-tube it again, this time a friend of mine who used to be an electrician biased it for me, I found that i could not get the amp up to the proper bias voltage needed for the tubes I had purchased. What could the possible problems be, and what would an estimate be for repairs?

7/10/2000 6:50 PM

Tom

Can't get enough power for proper Bias

I own an older Marshall JCM900 Head in covered in the old White Tolex. My problem is that I can't seem to get a good tone out of it. It seems to be tired and only gives a weak tone. I had the amp re-tubed and re-biased, and that helped a little but when I went to re-tube it again, this time a friend of mine who used to be an electrician biased it for me, I found that i could not get the amp up to the proper bias voltage needed for the tubes I had purchased. What could the possible problems be, and what would an estimate be for repairs?

Replies:

Peter S This perfectly normal. Part of bias... -- 7/10/2000 8:43 PM