Simple Electret Mic Preamp

Description


This simple circuit will allow you to convert an electret mic signal into a dynamic mic signal. This is usefull when you need to plug a computer microphone into a stereo or mixer. Since electret microphones require power, this circuit supplies power to the microphone and amplifies the signal.

Circuit Diagram


Parts List


Part QTY Description Value
R1,R3 2 1/4W 5% RESISTOR 10K
R2 1 1/4W 5% RESISTOR 100K
C1,C2 2 CERAMIC CAP 0.1uF
Q1 1 NPN TRANSISTOR 2N3904
MIC 1 ELECTRET MICROPHONE (or 3.5mm jack for connection)  

Construction


Due to it's low parts count, this circuit can be easily constructed on perf board or even directly soldered together. It can be housed in the actual microphone itself or a separate enclosure.

Circuit: