Yup. Otherwise he's dead, just as you say.
Cheers
Phil Hobbs
It might be better to use a microphone, and (in the preamplifier stage) use a quartz crystal resonator as a filter. The Q is so high, though, that you'll probably not get much pickup until you damp the crystal (with a parallel resistor).
There's lots of filter circuits in op amp cookbooks that will work, just be aware that the crystal doesn't pass DC current.
The feedback impedance of a 32 kHz crystal is usually not resistive at the oscillation frequency, but inductive (so the best gain ISN"T exactly at the oscillation frequency of the crystal-plus-capacitors in a resonator).
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