Checking the bias on my FRIEDMAN KS JMP 2203

[JMP/HBE]

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[JMP/HBE]

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[PFDarkside]

Re: Checking the bias on my FRIEDMAN KS JMP 2203

Did you have Friedman mod your Marshall (or get it pre-modded)? What year?

[JMP/HBE]

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[LLL]

Re: Checking the bias on my FRIEDMAN KS JMP 2203

Geez that's too easy - gotta bias the manly way - by installing a 1Ohm resistors, sticking the multimeter probe on pin 3 of powertube sockets and then probe the 1Ohm resistor, then doing some simple math!

[dystrust]

Re: Checking the bias on my FRIEDMAN KS JMP 2203

My 2525H is cathode bias, but I like to bias the 2555 to 35-36ma as well. Biased any hotter than 37 and it gets overly bassy and even more uncontrollably loud, any colder than 34 it gets brittle bright.

What year?

It's a 'K' serial, so 1978.

[JMP/HBE]

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