That’s what [Matt] from DIY ... DIY USB-C Microphone. He was able to source the same microphone capsule that can be found in his high-end, $600 CAD E100S, and built a simple pre-amplifier ...

along with a low-cost condenser microphone with a transistor-based preamplifier and an LM386 op-amp for the speaker circuit. In the ESP32 module the built-in DAC and ADC are used for audio in and ...