Category Archives: Pre Amplifier
Low Noise Portable Mic Preamp
This is the circuit diagram of portable mic preamp. This circuit consumes low current supply (about 2mA), so will have a long battery life for supplying the circuit. Harmonic distortion is about 0.1% @ 1V RMS output for all frequencies. Maximum input voltage (level control cursor set at maximum) = 25mV RMS. Maximum input voltage… Read More »
HiFi Audio Pre-amp
This is a HiFi pre-amplifier circuit diagram with low noise output. Very wide range frequency from about 10Hz until up to 100Khz will be gained by this preamplifier for maximum audio performance. This circuit uses BC550C / BC560C transistors as active component. Use regulated power supply 15VDC for maximum result.
Stereo Electret Mic Preamplifier
This a simple stereo electret microphone pre amplifier circuit. The below design diagram is the design for single channel, but the design of PCB layout is for stereo design og electret mic pre amp. For maximum performance, better quality, use solid capacitors or film capacitors and metal film resistors (1% tolerance). schematic diagram:
Low Impedance Microphone Amplifier
This is the circuit diagram of low impedance microphone amplifier. The circuit designed for use with low impedance (~200 ohm) microphones. It will work with regulated voltages between 6-30VDC. If you don’t build the impedance adapter part with T1, you get a microphone amplifier circuit for higher impedance microphones. In this case, you should directly… Read More »