Well the 10mH choke has a much better chance of resonating in the audio band than a tiny 100uH...Using component values a hundred-fold out isn't normally successful.
However i don't understand how on earth i'm to find the correct frequency for the inductor to increase the voltage?
1. Look up or measure the capacitance C of the piezo element.2. Calculate the parallel LC resonant frequency in Hz using f = 1/(2*PI*sqrt(L*C)).
What is the Q of the inductor? Power inductors are not normally suitable for RF applications like this.
...The inductor and piezo is in the 5v output of the arduino. When i measure across the piezo i get around 3.3v ...However when measuring the AC voltage i only get half of what's inputtet through the waveform generator, any guess what's wrong?