Birdbox Piezo Disc Microphone

Projects General Guidance
1

I have a couple of birdboxes and want to be able to record the sound inside from with a piezo speaker mounted on the outside of the box.

How do you record sound from the piezo, is this going to be the case of taking multiple readings from the ADC from the piezo over time? If so, do i need to amplify this signal first? And what sample rate should it be?

I want to be able to eventually pass this recording (data) over wifi using an ESP8266 or ESP32 but i want to be able to add at least 2x piezo's to the same circuit, is it possible to sample 2x piezo's and maybe buffer them? I would like to have an webpage on the ESP (receiving unit) allowing to play through the browser, is this possible?

I thought of a simple 2x ESP system, 1x piezo being read through ADC and sent over to another unit with a DAC that could maybe drive a speaker, would that work for one unit?

Can someone point me in the right direction? Most articles seem to be using a piezo as a speaker to play a melody with the Tone library or similar.

Thanks

2

A microphone would be a much better choice for recording sounds, especially if you want better than minimal sound quality.

There are some inexpensive microphone/amplifier modules that cover the audio spectrum nicely. You will need an amplifier in either case.

The nice thing about Arduino is you can try things on the bench and decide if it has any chance of working, before committing to a design.

And what sample rate should it be?

At least twice the highest frequency on the input, and also of interest (look up Sampling Theorem and Nyquist Criterion). Don't even bother with small Arduinos like the Uno, as they don't have enough memory to record sound.