Steve found another printed circuit board with the exact same circuit in his BM-800.

The electrolytic cap can be anywhere from 220 to 1000 uF at 16 V or more. It needs to be small enough to fit into the mic. You could flip this PCB over for more height if needed.


The small NP0 or C0G ceramic cap can be 10 to 40 pF at 16 V or higher. With a larger capsule, these mics are too loud. The small cap reduces the volume and distortion. The larger the cap, the quieter and less distortion. 22 or 27 pF works well for me.


You may need to swap the wires connected to pads N2 and N3 if your BM-800 is out of phase with your other mics. Most BM-800s are.