DIY Binaural plug-in powered (3V) electret microphone.
Electret Condenser Microphone: Primo EM272 matched-pair omni-directional. https://micbooster.com/primo-microphone-capsules/199-primo-em272.html
Microphone Specification – https://micbooster.com/datasheets/EM272.pdf
Note that:
1. You can connect the ground core to the microphone capsule metal shell for grounding.
2. The microphones operational voltage is between 2-5V with maximum of 0.5mA current. For supplying the build in microphone capsule’s JFET preamp with 12-48V phantom power supply (instead of 3V plug-in power), additional circuit is needed such as Step-down 5V @0.5mA, DC coupling, filtering etc.
3. Additional insulation may required at the end of the soldered microphone terminal-cable to avoid exposed red positive cable core making contact with the microphone capsule metal shell and other cable cores (= noise!).
The binaural human head size sphere shell is fabricated with PETG through 3-D printing. I will share more information on this once the ‘binaural sphere’ project is completed and officially documented.
Specifications:
- Primo EM272 Electret Microphone (1 set matched-pair = 2x)
- Shielded balanced microphone cable (1 meter)
- Audio connectors TS or TRS or XLR or Phono or JST (2 unit)
- Microphone capsule vent protector – optional (2 unit)
- Some solder flux and soldering tools
- Heat shrink tube sleeve (50mm x 2 unit yellow color, 50mm x 2 unit blue color)
- Multimeter – optional (1 unit)
- Head size sphere shell – hollow (1 unit)
This development is part of Nada Sfera project inspired from Acoustic Commons 2021 Workshop and Locus Sonus
