New low cost RTA-M microphone couples brilliantly with the DriveRack PA or anywhere a good quality reference mic is needed. Features: Polar pattern: Omni Element: Back Electret-Condenser Frequency Response: 20Hz-20kHz Impedance: 250 Ohm +-30% @ 1kHz Sensitivity: -63dB +-3dB Operating Voltage: Phantom Power-9v Comes in protective case with clip