User Manual

Chapter 5: Pro Tools Systems 45
HD I/O Audio Interface
HD I/O is a multichannel digital audio interface
designed for use with Pro Tools HD systems.
HD I/O features extremely high quality 24-bit an-
alog-to-digital (A/D) and digital-to-analog (D/A)
converters, and supports sample rates of up to
192 kHz.
HD I/O comes in three standard configurations:
• 8 x 8 x 8 (8 analog in, 8 analog out, and 8 digital
in and out)
• 16 x 16 analog in and out
• 16 x 16 digital in and out
You can also add or remove HD I/O Analog Ex-
pansion cards (ADC and DAC) and HD I/O Digi-
tal Expansion cards for custom configurations.
HD I/O Features
HD I/O provides up to 16 discrete channels of
Pro Tools input and output, with 4-segment LED
meters for input and output.
Analog I/O
• Up to sixteen channels of 24-bit D/A and A/D
converters for superior analog input and output
at sample rates of 44.1 kHz, 48 kHz, 88.2 kHz,
96 kHz, 176.4 kHz, and 192 kHz with Analog In
and Analog Out HD I/O cards
• Soft Clip and Curv limiting circuits to protect
against clipping on analog input
Digital I/O
• Up to sixteen channels of 24-bit digital I/O, us-
ing AES/EBU, TDIF DB-25, or Optical at sam-
ple rates of 44.1, 48, 88.2, 96, 176.4, and
192 kHz with a Digital HD I/O card
• Real-time sample rate conversion on digital in-
puts with a Digital I/O card (up to sixteen chan-
nels of AES/EBU, Optical, or TDIF)
• Support for S/MUX Optical for sample rates of
88.2 kHz and higher
• Support for 2 channels of S/PDIF Optical
(enclosed) with sample rates of up to 96 kHz
• 2 channels of AES/EBU I/O (enclosed) with
support for sample rates up to 192 kHz
• 2 channels of 24-bit-capable S/PDIF I/O
(enclosed) with support for sample rates up to
192 kHz
Synchronization
• Loop Sync input and output for connecting addi-
tional Avid HD audio interfaces and peripherals
• External Clock input and output for synchroniz-
ing HD I/O with external Word Clock devices
Expandability
• Optional addition of I/O cards to expand analog
or digital I/O
• Simultaneous use of multiple Avid HD audio in-
terfaces to further expand system input and out-
put
For more information, see the HD I/O Guide.