Specifications

Chapter 2: Expanded Pro Tools|HD Systems 9
Connecting
Audio Interfaces
All HD-series audio interfaces require DigiLink
connections. When using multiple interfaces,
you must also connect Loop Sync between all
HD-series audio interfaces. When using multi-
ple Legacy interfaces (MIX-series I/O such as the
888|24 I/O and 882|20 I/O) you must connect
Slave Clock to all MIX-series audio interfaces.
Recommended Ordering of Interfaces
If your setup includes different types of audio
interfaces, install them in the following order:
192 I/O or 192 Digital I/O Use as the primary au-
dio interface. These interfaces provide the high-
est fidelity clock source for your system.
96 I/O Use as the primary interface (if a 192 I/O
or 192 Digital I/O is not installed), or as an ex-
pansion interface connected to the Expansion
port of the primary interface.
96i I/O Use as the primary interface if no other
HD-series interfaces are installed, or as an ex-
pansion interface connected to the Expansion
port of another HD-series interface.
Legacy Peripherals See “Using Legacy Audio In-
terfaces” on page 12.
DigiLink
The DigiLink cable connects HD cards and au-
dio interfaces. A single Digi-Link connector car-
ries up to 32 channels of bidirectional audio in-
formation. These 32 channels are broken up
into 2 groups of 16 channels: Group A = Chan-
nels 1–16, Group B = Channels 17–32.
The maximum number of DigiLink cables sup-
ported on a single system is eight. This allows up
to 128 channels of I/O with eight HD-series au-
dio interfaces: four connected directly to an HD
card and the remaining four connected to the
expansion ports of the first four.
◆ Use the 12-foot DigiLink cable included with
each Pro Tools|HD card to connect the card to a
Digidesign audio interface. The primary audio
interface, which functions as the Loop Sync
master for other interfaces in the system, must
be connected to the HD Core card. You can pur-
chase optional DigiLink cables of differing
lengths (25-foot, 50-foot, and 100-foot), de-
pending on the needs of your studio configura-
tion.
◆ Use the 18-inch DigiLink cable, included with
each HD-series audio interface, when connect-
ing a secondary HD-series audio interface to the
Expansion port of another HD-series audio in-
terface.
If you have at least one 192 I/O or
192 Digital I/O in your Pro Tools system, it
should be the primary audio interface and
Loop Sync master.