Specifications

Chapter 1: Introduction 1
Chapter 1: Introduction
Avid
®
HD I/O is a multi-channel digital audio
interface designed for use with Avid HD Native
and Pro Tools|HD hardware. HD I/O features
24-bit analog-to-digital (A/D) and digital-to-an-
alog (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 analog (ADC and
DAC) and digital cards for custom configura-
tions.
HD I/O Features
HD I/O provides up to sixteen discrete channels
of audio input and output, each with a 4-seg-
ment LED meter. The total available analog and
digital I/O is dependent on the configuration of
Analog and Digital Expansion I/O cards in-
stalled in HD I/O.
Analog I/O
• Up to 16 channels of 24-bit D/A and A/D con-
verters 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 16 channels of 24-bit digital I/O, using
AES/EBU, TDIF DB-25, or Optical at sample
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
inputs with a Digital I/O card (up to sixteen
channels 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 (en-
closed) 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 (en-
closed) with support for sample rates up to
192 kHz
Synchronization
• Loop Sync input and output for connecting ad-
ditional Avid HD audio interfaces and periph-
erals
• External Clock input and output for synchro-
nizing HD I/O with external Word Clock de-
vices
Expandability
• Optional addition of I/O cards to expand ana-
log or digital I/O
• Simultaneous use of multiple Avid HD audio
interfaces to further expand system input and
output