Bias on Marshall JCM 900 SL-X 100 W

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Mats A
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Bias on Marshall JCM 900 SL-X 100 W

Post by Mats A » Mon Oct 07, 2013 12:15 am

My brother has converted my Marshall JCM 900 SL-X 100 Watt who originally had 5881 valves to EL 34´s using a Marshall conversion manual i got plus an SL_X schematic with EL 34´s i got at the Marshall factory in 1993. Question is how should the bias be set? According to a schematic on Dr Tube it should be set at -45. We can only get it to 38.
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stef
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Re: Bias on Marshall JCM 900 SL-X 100 W

Post by stef » Mon Oct 07, 2013 12:07 pm

38 or -38mv?
What's the plate voltage?
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