Test fitting capsules


Gluing capsule #1 to the saddle


Solder wires to both capsules before gluing.

The capsules are spaced 3 quarters

(25¢ coins) apart.


The DPDT On-Off-On switch is glued to the frame with handle protruding  thru a slot in the body sleeve. ====>

Switch wiring. Front capsule (red & white) connects straight to input of electronics. Rear capsule (blue & green) connects thru polarity reverse switch.


Electronic mods are the same as described in previous BM800 mods, consisting of an added 220µF/25V electrolytic capacitor to filter the output of the voltage regulator, and a 22pF capacitor from drain to gate of the FET to reduce gain and distortion, and raise the maximum sound pressure level before overload. A blue LED was added in series with the 22K resistor in the voltage regulator just for fun and to show when phantom power is on.

The finished mic sounds like other mics using this CM-012 capsule, with a bit of presence lift in the upper mids. The patterns of this pair of capsules are well matched, with a deep null to the sides and top of the mic in fig-8, and uniform omnidirectional pickup.

In all, a useful and versatile mic for little money, but not a quick build, with a lot of filing to get pieces to fit. If I build another one, I’ll avoid some of the pain. For instance, I found the grille screens are glued, not soldered in place, and the top screen can be popped out to access the capsules from above. And perhaps drill and tap alternate headbasket attachment screws before putting the switch in place.