On Jul 13, 11:30 pm, lw1ecp wrote:
I guess a look at the guts of an old piezo tweeter could give you a
hand.

I had never heard of a piezo tweeter before your post. They sound like
a different type of device than what I am pursuing. I need an earpiece
with very high impedance, one that can work off of the nominal
potential a crystal radio circuit can produce.

But hey, thank you for the feedback, my world is ever so slightly
larger than before...