Electret Condenser Microphone Preamplifier by BC650C or BC549C - EEWeb
Electret condenser microphone amplifier for use in microcontroller projects - Do It Easy With ScienceProg
DIY JFET Mic Pre: DIY JFET Mic Preamp and Beyond! | Tape Op Magazine | Longform candid interviews with music producers and audio engineers covering mixing, mastering, recording and music production.
Lavalliere Microphone Preamplifier
Amazon.com: Condenser Microphone Kit with Pre-Amp [ Unassembled version ] 9VDC : Musical Instruments