Chapter 2: Pro Tools | HD I/O Overview 7
Pro Tools | HD I/O Back Panel
Although the HD I/O is a sixteen-channel audio in-
terface, it has up to 94 inputs and outputs available
through its various back panel
connectors.
HD I/O comes in three standard configurations:
• 8 x 8 x 8 analog and digital in and out
• 16 x 16 analog in and out
• 16 x 16 digital in and out
Input and Output Cards
The HD I/O features four bays for HD I/O
Expansion cards. With the standard 8 x 8 x 8 con-
figuration, bays 1–3 contain Analog In, Analog
Out, and Digital I/O cards, respectively. The fourth
bay (as shown in this 8 x 8 x 8 configuration) is an
expansion bay, for which you can purchase an ad-
ditional Expansion I/O card of your choice.
By installing an optional AD Expansion card, DA
Expansion card, or Digital Expansion card, you
can add even more I/O capacity (up to a maximum
possible 110 inputs and outputs). See Chapter 5,
“Adding or Removing I/O Cards.”
HD I/O Back Panel, 8 x 8 x 8 configuration shown
964530300294856
WORD CLOCK
LOOP SYNC
PRIMARY PORT
EXPANSION PORT
IN
OUT
AC ~ 100-240V;50-60HZ; A
S/PDIF
IN
OUT
AES/EBU
INPUT
AES/EBU
OUTPUT
OPTICAL
IN
OUT
ACCESSORY
1
2
3
4
5
6
7
8
ANALOG INPUT
+4 dBu BALANCED
-10 dBV BALANCED
1
2
3
4
5
6
7
8
ANALOG OUTPUT
BALANCED
DIGITAL I/O
AES/EBU
ADAT
IN
TDIF I/O
ADAT
OUT
Bay 2: Analog Out card
Bay 1: Analog In card
Bay 3: Digital I/O card
Bay 4: Empty for Optional card
Enclosure
Input and Output cards for 192 I/O are not
supported in HD I/O.