Hi!

I see the pjrc shop offers a mic that fits the audio board (3.x). Would any other electret mic work, for example this one?

https://www.electrokit.com/produkt/e...-o9-7-x-6-7mm/

translation of the description:
Miniature electron-type microphone. Omnidirectional. High sensitivity and even frequency response. Very reliable and shock resistant. Requires active drive.

* Diameter: 9.7mm 0.2mm
* Height: 6.7mm 0.2mm
* Sensitivity: -60dB
* Maximum input level SPL 110dB
* Impedance: 2.2kohm 30%
* Supply voltage: 4 - 5VDC (max 10V)
* Power consumption: <0.5mA
* Termination: soldering iron (10mm)
* Direction: omnidirectional

Thanks!