pMic

thingiverse

Create a printable A-B Stereo Microphone with variable stereo width using Panasonic WM61 capsules. I searched for a suitable mic without a built-in recorder and found a low-cost homebrew solution at http://www.wildlife-sound.org/equipment/technote/micdesigns/. The microphone's on/off switch is near the audio jack, with a gain boost as its secondary function, convertible to a damp by swapping two resistors in the circuit. The preamp circuit isn't necessary if your recorder has phantom power, but the 9V battery increases headroom for louder signals and powers the capsules conveniently. The distance between the capsules and preamp should be short. I'm satisfied with the sound quality, and you can download audio examples from https://github.com/Piesi/pMic/tree/master/docs/audio_examples. It requires 2-4 WM61 electret condenser capsules, M4 bolts, M3 bolts, an M3 bolt, M4 nuts, enameled copper wire, a simple preamp circuit, a 9V battery, and rubber bands for assembly. The printing parts are easy, but the case parts need support. The preamp circuit is based on a TL072 op-amp and measures 69x18mm. All other information can be found in the provided files.