Actually... nothing. The ACX was in our "boneyard" of scrapped amps and I've removed the power amp section for use in a gainclone I'm putting together. The B300s used to use a LM3886 circuit almost identical to the recommended circuit on the 3886's spec sheet from National Semiconductor and I wanted to see how the ACX power amp compared. Plus, it'd be nice to know where everything was on the board without tracing it out manually.
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