Electret microphone capsule schematic. wdwd [CC BY 3.0] The electret condenser microphone that I bought for pennies is a capacitor microphone, so why is there no high voltage supply? The answer ...

The entirety of the build is minimal, consisting of a GY-MAX4466 electret ... a capacitor for power line noise suppression. [Stephen] uses various enclosures from Thingiverse for the microphone ...