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solarburnDSL50 · 10-07-2008, 12:37 PM

Part of biasing your DSL is getting plate voltage too. You figure this number and you can get your correct bias number. DSL's run plate voltage from 450 to 500 with EL34's usually somewhere in between. Marshall recomends 40 to 45 bias. I set mine cooler at 36 with Tung Sol EL34B's.

Example formula - 25 watts disipation divided by lets say 450 plate volts = .055
Then multiply .055 times 60 or 70% depending how hot you want to run the tubes. .055 x .6 = .033 .055 x .7 = .038.

So at 60% your bias number is 33. At 70% your bias number is 38. Eurotubes didn't show how to check for voltage in the DSL vid. He just set the bias which is what you do after getting the plate voltage and crunching the numbers per the formula. He does show how with the JCM 800 vid though.

10-07-2008, 12:37 PM	#19 (permalink)
solarburnDSL50 Senior Member Join Date: Aug 2008 Location: WashingTone Posts: 130	Re: Just Got New Tubes For My DSL 100 Part of biasing your DSL is getting plate voltage too. You figure this number and you can get your correct bias number. DSL's run plate voltage from 450 to 500 with EL34's usually somewhere in between. Marshall recomends 40 to 45 bias. I set mine cooler at 36 with Tung Sol EL34B's. Example formula - 25 watts disipation divided by lets say 450 plate volts = .055 Then multiply .055 times 60 or 70% depending how hot you want to run the tubes. .055 x .6 = .033 .055 x .7 = .038. So at 60% your bias number is 33. At 70% your bias number is 38. Eurotubes didn't show how to check for voltage in the DSL vid. He just set the bias which is what you do after getting the plate voltage and crunching the numbers per the formula. He does show how with the JCM 800 vid though. __________________ DSL50 - Voodoo modded Fender Tele GT HH coil split 212 G12K-100/V30 Pedals just for the Marshall: Bad Monkey Boosta Grande Wah Aphex Xciter in loop Delay in loop