The optional RTA-M real time audio analyzing mic is the perfect accessory tool for the DriveRack PA series (PA, PX, PA+, PA2) and 260. Used in conjunction with the System Setup Wizard and Auto EQ Wizard the RTA-M is ideal for optimizing the sound quality of even the most difficult of acoustic environments. The RTA-M is an omni-directional, flat frequency measurement microphone specially designed for the Driverack series to pick up all frequencies from 20 Hz to 20 kHz, ensuring accurate "pinking"/real-time analysis of your audio. It runs on phantom power (supplied by the Driverack units) and comes with a clip and case.