Specifications

96 I/O Guide 4
Loop Master LED
The LOOP MASTER LED indicates which
Pro Tools|HD audio interface is the master
Pro Tools peripheral. Loop Master defaults to
the first Pro Tools|HD I/O connected to the
“core” card. On Pro Tools|HD (for PCIe), this is
the Accel Core card. On Pro Tools|HD (for PCI),
this is the HD Core card.
Loop Master will always be lit when only a sin-
gle interface is present, regardless of the syn-
chronization mode.
Only one Pro Tools|HD I/O can be Loop Master
at a time. When you change the clock source to
an external clock on a particular Pro Tools|HD
audio interface, that interface will automatically
become the Loop Master and all other
Pro Tools|HD audio interfaces in the Loop Sync
chain will be switched to Loop Slave mode. The
Loop Master LED will be continuously lit on the
current Loop Master peripheral only, and unlit
on all other peripherals.
Sync Mode LEDs
The SYNC MODE LEDs indicate the Clock
Source choice as configured in Pro Tools:
INT (Internal) The 96 I/O standard clock setting,
this mode illuminates when the 96 I/O sample
clock is generated by its internal crystal oscilla-
tor, as determined by the session Sample Rate.
DIG (Digital) Indicates that an external
AES/EBU, Optical (ADAT), or S/PDIF device is
providing system clock.
LOOP Indicates that the 96 I/O is slaving to an-
other Pro Tools|HD I/O through Loop Sync.
EXT (External) Indicates that 96 I/O is using the
EXT CLOCK IN port for system clock.
For more information, see the
Pro Tools|HD Get-
ting Started Guide
.
Input and Output LEDs and Meters
16 sets of four-segment LEDs indicate signal
level for each of the 96 I/O’s 16 channels.
These meters are calibrated at –42 dB, –18 dB,
–6 dB, and 0 dB, respectively.
Two additional LEDs, located to the left of the
meters, indicate whether the meters display in-
put or output levels; the meters indicate output
levels by default, and can be switched from
within the Hardware Setup dialog in Pro Tools.
0 dB is not to be confused with clipping; use
the on-screen meters in Pro Tools to deter-
mine whether a signal is clipping.