This small LJM module is a transistor preamplifier in pure Class A.It provides an efficient preamp section based on discrete components with the possibility of adding a potentiometer.. The module offers a wide dynamic range and the single-ended circuit generates little or no distortion. In terms of restitution, this translates into a warm and soft sound.

The module benefits from a good quality design, with the use of Nichicon capacitors, an adjustable LM317T voltage regulator and BC547 transistors. The volume control is done thanks to the integrated 50 KOhm logarithmic potentiometer.

On the power supply side, the module offers three-stage filtering. The first uses the LM317T regulator, the second an RC circuit and an inductor and finally the third an RC transistor filter. This provides a clean current, similar to that offered by a battery.