1974x PT replacement

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Re: 1974x PT replacement

Post by JMPGuitars »

80% is excellent, assuming all the values are correct. I wouldn't change it. Don't arbitrarily change stuff without good reason.

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Re: 1974x PT replacement

Post by foreverstrung »

Ya, I'm not going to change anything. Numbers are correct. I triple checked. Put the amp back together 100% and put it thru the motions for about an hour. Sounds fantastic. appreciate all the help
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Re: 1974x PT replacement

Post by geoff 1965 »

Well done! glad you are happy with it,I was surprised at the quite low 318 plate voltage and it looks like Marshall aimed at breakup with this design,the stock 91R bias resistor would drop the plate & cathode voltage even more!
1 x

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