Headset cardioid condenser microphone that is same as the Audio-Technica ATM37a model, but features a less power module. It is ideal for drummers, keyboard players or anyone requiring hands-free operation, featuring a comfortable, unobtrusive headband design with side-of-mouth pickup. Its belt-mounted power module operates on battery or phantom power. Its cardioid polar pattern improves isolation of desired sound source. The microphone comes supplied with a 1.4m long cable terminated with locking 4-pin connector for A-T UniPak wireless systems, a single AA battery for operation, and ATM128 and ATM125 windscreens. Frequency response: 40 Hz-15 kHz. Low frequency roll-off: 80 Hz, 18 dB/octave. Open circuit sensitivity: -55 dB (1.7 mV) (phantom), -56 dB (1.5 mV) (battery). Impedance: 200 ohms (phantom), 270 ohms (battery). Maximum input sound level: 146 dB (phantom), 132 dB (battery). Dynamic range: 111 dB (phantom), 97 dB (battery). Signal-to-noise ratio: 59 dB. Phantom power requirements: 11-52 V DC. Dimensions: 165 x 67 mm (headset), 84 x 63 x 22 mm (power module). Weight: 31 g (microphone), 139 g (power module).