SMALL POWER AMPLIFIER 2W MICROPHONE WITH SPEAKER Assembled Electronic Circuit : FA672 This circuit is a small amplifier which include pre-amplifier, condensor microphone and a loudspeaker. It is easy using and installation. Ideal as in class, meeting room etc. Power Supply : 4.5-12 Vdc. , Consumption : 300 mA max. @ 12 Vdc. Output Power : 2W.max. (using a loudspeaker 8? 2W/power supply 12 V/ 1.5 A. max.) Adjustable level sound by potentiometer. , S/N ratio : 80 dB (A weighted) , Frequency Response : 20 Hz to 20 kHz (-3dB) PCB dimensions : 2.34 x 1.42 inches.