Originally a bit of a flop from Boss, the FET Amplifier was made famous by U2's The Edge. It features a 2-band Baxendall tone stack and the Volume control is more like a gain control. Originals use 2 single opamps that are pretty hard to come by these days, so they've been replaced by a dual opamp. Pots are board mounted and it should all fit in a 1590B.
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