Hardware Hacking - Nicolas Collins

34 Nicolas Collins

Figure 1

Figure 2

Occasionally one finds condenser microphone elements with three wires instead
of two. This makes the job even easier. Instead of combing signal and battery
power on a single wire, one wire will be designated as the signal, and will
connect directly to the tip of the plug or pin 2 of the xlr; another will be labeled
“power” and connects to the “+” of the battery; the third (invariably the shield)
connects to both the connector ground and the battery’s “-“ terminal.

The mechanical packaging is trickier than the electronic wiring. The tiny electret
element can be glued into a plastic drinking straw or encased in heat-shrink
tubing, and the cable run down to a small box containing the battery, resistor,
capacitor, switch and jack. Or you can drill a hole in a small box, insert a plastic
grommet into which the mike fits, build-in the remaining components, and run a