Electret Condenser Microphone Preamplifier by BC650C or BC549C - EEWeb
Dynamic microphone amplifier using transistors
Lavalliere Microphone Preamplifier
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.