Re: [DESIGN] Piezo-Piezo to Piezo-Switch Adaptor (by Keith Raper)

[PFozz]

Circuits 1/3 are what you need.
It seems the “rim detection” part of your circuit isn’t sensitive enough, though.
You may try to reduce the R1 value (replace R1 by a pot to do it progressively).
 
Best.

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