Bridge-IT PRO - Ideal for STL, Studio-to-Studio, and Point-to-Multipoint (up to 6). NO computer needed! Has FULL control interface ON codec (screen, keypad, nav control), professional XLR connectors, stereo bi-directional (Encode & Decode), 2 relay inputs/outputs + RS232, remote control via computer GUI. Includes all Tieline algorithms (15khz Music, 22kHz MusicPLUS), MP2, AAC-Suite Algorithms, and Failsafe SD card reader (plays audio files for backup). - Requires two Tieline Units