STK series type amp bias adjust, how is it done?

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There has been a lot of talk about bias adjust in this forum lately. I currently own an amp that uses STK series modules (STK3062, STK1050 and STK1060). It is a technics su-c03.

I know that bias adjust on this type of amp is different from the procedure used in adjusting the bias on an amp with descrete components (emitter resistors and such). I wanted to know how I could go about adjusting the bias on this type of amp.

I have two trim pots to play with (left and right channel). I replaced them with a good quality trim pot, and set them to both 15 ohms, which i believe MAY be the factory setting. this amp has been through many hands and this may not be the factory setting, so i would like to know how to measure my bias current to have an idea at what its running and make the proper adjustments.

**please no talk about emitter resistors, this type of amp doesnt have any! ive read all the threads about bias adjusting, but they all apply to descrete component amps**
 
EchoWars said:
I suspect that the two pots you speak of are for DC offset. [/B]

Yup, those two trim pots are for DC offset! I assumed they were for bias adjust because i was told that some amps only have trim pots for bias adjust, the DC offset it controlled and eliminated automatically by the design of these type of amps.

well i opened my amp and while it was nice and warm, i was able to drop DC offset from about 160 millivolts and 180 millivolts to 0.0 +/- 0.5 millivolts on both channels.

thanks for clearing things up!
 
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