Condenser Microphone with Pre-Amp 9VDC Electronic Circuit Kit : FA648 The board is a small circuit with an on-board condenser mic and preamp. This microphone-condenser pre-amplifier circuit.This circuit is small and has only few components.This circuit has pre-mic and mic-condenser, it is high sensitivity than normal circuit. Requires 9 VDC , Current Consumption : 5mA.max PCB size : 0.67 x 1.50 inches Comes with the schematic diagram It has higher sensitivity than normal circuits