The optional RTA-M real time audio analyzing microphone is the perfect accessory tool for the DriveRack PA, DriveRack PA+ 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 20Hz to 20kHz , 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.