Specifications

Chapter 2: Expanded Pro Tools|HD Systems
10
Expanded Systems Guide
The 96 I/O and standard 192 I/O are examples of symmetrical I/O, where there are the same number of input
channels as output channels. For example, there are 8 analog inputs and 8 analog outputs. Though these I/Os
provides many analog and digital connectors on their back panels, they support a total of 16 channels of si-
multaneous, discrete input and output. This means you can be listening to or recording as many as 16 chan-
nels of input while simultaneously monitoring or sending as many as 16 channels of output through a single
I/O.
The 192 I/O can be expanded by adding a 192 A/D or 192 D/A Expansion card to increase the number of an-
alog inputs or analog outputs to 16. Expanded 192 I/O interfaces are an example of asymmetrical I/O when
they have a different number of input channels or output channels. For example, when a 192 A/D card is in-
stalled on a standard 192 I/O, the I/O now has 16 analog inputs and 8 analog outputs.
On Expanded 192 I/Os, the maximum number of simultaneous, discrete inputs and outputs is still 16.
Because of the way in which 192 I/O interfaces can be expanded, the maximum number of channels of digital
or analog I/O possible with an expanded Pro Tools|HD system depends on whether you use digital or analog
connections, and whether you require a symmetrical or asymmetrical number of input and output channels,
as explained in the following examples:
Maximum I/O Configuration Examples
Pro Tools|HD System with Ten Interfaces (Session Sample Rates Up to 96 kHz)
Digital Up to 160 input and output channels (requires ten 192 Digital I/O interfaces)
Analog Up to 120 simultaneous channels of input and output. Requires the following:
• Five 192 I/O interfaces modified for 16 analog inputs and 8 analog outputs (requires adding an A/D card
to each interface)
• Five 192 I/O interfaces modified for 8 analog inputs and 16 analog outputs (requires adding a D/A card
to each interface)
Pro Tools|HD System with Eight Interfaces (Session Sample Rates Higher than 96 kHz)
Digital Up to 128 channels of input and output (requires eight 192 Digital I/O interfaces)
Analog Up to 96 simultaneous channels of input and output. Requires the following:
• Four 192 I/O interfaces modified for 16 analog inputs and 8 analog outputs (requires adding an A/D card
to each interface)
• Four 192 I/O interfaces modified for 8 analog inputs and 16 analog outputs (requires a D/A card added
each interface)
If you need more analog inputs and do not need all available analog outputs, use more A/D cards and fewer
D/A cards. Conversely, to increase output capacity, use more D/A cards instead of A/D cards.