i made a microphone out out of an electret mic capsule that matt found in sudo w/the following circuit:

                           10u
    +---------o-------------||------o-----------------  HOT    (2)
    |         |                     |
    |         |-                    |
    |      CAPSULE                 22k
    |         |+                    |
    |         |            10u      |
    |         o-------------||------|------o----------  COLD   (3)
   2k2        |                     |      |
    |        2k2                    |     22k
    |         |                     |      |
    |         o--330R---o----o------o------+
    |        +|        +|    |+
    |        10u       12V  10u
    |        -|        -|    |-
  --o---------o---------o----o------------------------  GROUND (1)

and it works well! very responsive

-it must have phantom power (48V from mixer/mic preamp)

-"12V" in the diagram is a 12v zener diode

- 10u in the diagram are plastic film caps. (if you only have 10uF electrolytic caps also use 100nF in parallel, like i did))

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