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Wojtek,

I use 15 of the attached as input pads for a MIDI drum kit. The pot
is a sensitivity control. The opamp is wired as a peak detector with a
nominal output of 2.5V. Normally the 1uF cap is discharged by the
100k. When the pad is hit, the 1uF charges to the peak value, which
is measured by the ADC (which then turns to an o/p to discharge the
cap quickly). This way the volume (or effect) can be linked to the hit
strength/speed

wbr

Happy New Year
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