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Hoffman Amps Forum image Author Topic: AB165 Bias upgrade  (Read 1513 times)

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Offline angelodp

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AB165 Bias upgrade
« on: February 29, 2020, 01:05:48 pm »
Hi, do I understand Doug's article on Bias upgrade correctly to include the AB165. The AB 165 has a balance system and i want to put in a proper Blackface Bias.  I read that I need to install two 220k resistors and i see the correct position, in addition to other wiring changes and cap upgrade. My question is, do i need to remove the other two 220k's that are further down the line.
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Offline sluckey

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Re: AB165 Bias upgrade
« Reply #1 on: February 29, 2020, 01:31:00 pm »
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A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!
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