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harp · 08-13-2009, 10:59 PM

Just thought I would update everyone. After taking the amp to the amp tech I found out that the "matched" quad of tubes that I got from JJ was not so matched. Because I was only checking the bias on one of the tubes, I had it biased way to hot. The amp tech switched the tubes around so that both sides were more or less balanced, then re-biased. The thing still runs pretty hot, but it's not near as bad as it was. Thanks for all the helpful advice.

08-13-2009, 10:59 PM	#57 (permalink)
harp Junior Member Join Date: Jun 2009 Posts: 18	Re: JCM 900 6l6 to EL34 Conversion problems Just thought I would update everyone. After taking the amp to the amp tech I found out that the "matched" quad of tubes that I got from JJ was not so matched. Because I was only checking the bias on one of the tubes, I had it biased way to hot. The amp tech switched the tubes around so that both sides were more or less balanced, then re-biased. The thing still runs pretty hot, but it's not near as bad as it was. Thanks for all the helpful advice.