The 888|24 I/O is an audio interface used with Pro Tools (requires PT 4.1 or later). It connects to any of the following cards: PT Project PCI, Disk I/O PCI, d24 Audio Card.GeneralAnalog Inputs/Outputs: Actively balanced XLR connectors; internally switchable between +4dBu and -10dBV operating levelsAnalog Level Trimming: via recessed trim pot, accessible from front panelDigital I/O's AES/EBU: 8 channels; balanced XLR connectorsDigital I/O's S/PDIF: 2 channels; coaxial RCA connectorsSample Rate: 44.1kHz or 48kHz +/-10ppmClock Reference: Super Clock 256x sample clock; In/Out; BNC connectors; additional clock references supported via Digidesign's Universal Slave Driver, SMPTE Slave Driver, Video Slave Driver and other optional synchronizersNominal Operating Level: +4dBu; factory calibrated at -18dB headroomA/D Specifications (typical)SNR (signal-to-noise ratio): -113dB (balanced, A-weighted), -110dB (unweighted)THD: 0.003% -0.01dB @ 1kHz 20Hz-20kHz (band-limited)Maximum Input: +26dBFrequency Response: 20Hz-20kHz +/-1dbClock jitter: <40pS RMS 22Hz-22kHz BWD/A Specifications (typical)SNR (signal-to-noise ratio): -110dB (balanced, A-weighted), -107dB (unweighted)THD: 0.003% -0.01dB @ 1kHz 20Hz- 20kHz (band-limited)Maximum Output: +26 dB/channel (bridging loads)Frequency Response: 20Hz-20kHz +/-1dBOutput Impedance: 50ohms typical (45 min, 55 max)Input Impedance: 24 kohms typicalPhysical SpecificationsPower requirements: 90-260 VAC, 47-63 Hz; 30 VA; auto-switchingWeight: 7 lbs, 9 oz (4.1 kg)Dimensions: 2u external rackmount device; 19" x 3.5" x 9.75" (48.26 cm x 8.89 cm x 24.77 cm) black anodized finish