The ACTIVE-1 Provides seamless A/B switching of input sources and speaker systems and includes USB I/O for direct digital audio recording and playback when connected to a computer audio system. The ACTIVE-1 allows monitoring of four stereo input sources via four stereo outputs and delivers a full complement of audio monitoring functions, including: precision volume control, mono summing, mute, and dim. A footswitch-activated talk-back function, complete with on-board condenser microphone and selectable routing, makes the ACTIVE-1 the ideal solution for a broad range of studio production applications. Dimensions W x D x H: 13.0 in. x 7.5 in. x 5.0 in. ( 330 mm x 191 mm x 127 mm; Weight: 2.0 lb ( 0.9 kg) Power Requirements: Supplied 9 Volt DC Power Supply