Specifications

192 Digital I/O Guide 4
Sync Mode LEDs
The Sync Mode LEDs indicate different clock
source modes for each I/O (as set with the Clock
Source choice in Pro Tools Hardware Setup dia-
log).
Only one HD I/O can be Loop Master at a time.
When you change the clock source to an exter-
nal clock on a particular HD I/O, that HD I/O
will automatically become the Loop Master and
all other HD I/Os in the chain will be switched
to Loop Slave mode. The Loop Master LED will
be lit on the current Loop Master peripheral
only, and unlit on all other peripherals.
For more information, see “Synchronization
Mode and Clock Source” on page 16.
Meters
These four-segment LEDs indicate signal level
for each of the sixteen channels. The top row of
meters indicates input levels, and the bottom
row shows output levels. These meters are cali-
brated at –42 dB, –18 dB, –6 dB, and 0 dB, respec-
tively.
192 Digital I/O front panel
Note that 0 dB is not to be confused with
clipping; use the on-screen meters in
Pro Tools to determine whether a signal is
clipping. See the
Pro Tools|HD Reference
Guide
.