A small and useful circuit that amplifies the microphone signal to line level. It accepts dynamic and condenser microphone with internal supply. It also operates the 3 pole-condenser microphones. It has two inputs with different sensitivity. The circuit is based on the integrated circuit LM833 that ensures low noise, low distortion, high sound quality and reliability. The gain can be adjusted by a trimmer to avoid overloading and distortion. V 9 VDC PCB 44x70mm