[Swenrekcah]

From what they said, an incoming RF signal is converted to acoustic signal. That acoustic signal is probably not in the human audible range. It’s that signal which is filtered and then amplified with this new device, IIUC.

[imhoguy]

I hope won't produce some nasty coil whine.

[jacquesm]

It is thousands of times higher than the highest frequency that you can hear. That doesn't rule out interference with another frequency leading to a difference that is in the audible range but all things considered this should not happen. Also, there are no coils involved, it's piezo-electric.