PRE-AMP MIC CONDENSOR circuit is simple, consisting of 2 levels.
with wide dynamic regions, small noise, and can with a long cable about 50 meters.
-all capacitor (elco) using 25-volt
-to avoid the buzzing sound, use a good regulator supplay
-This circuit can provide voltage 6-20volt
This circuit uses low noise transistors are type types:
BC 650 C but the transistor is hard to find, so you can replace it with 109 BC is no less good.
This condenser mic element in it is a very sensitive microphone, and to use this mic condenser
required voltage between 2-10 volts, for that we can resistors in series with 1K-10 K ohms,
in the picture above the tide 1k ohms.