User guide

Avid Mbox Pro User Guide22
Word Clock
Mbox Pro provides Word Clock In and Out con-
nectors on the back panel that let you synchronize,
or “clock” Mbox Pro to industry standard Word
clock. Word clock is used to synchronize a wide
range of devices such as non-linear video systems
and other types of equipment typically found in
professional audio facilities.
With both Word clock input and output, your
Mbox Pro-equipped system can act as Word clock
“slave” or “master.”
To connect Word clock to Mbox Pro:
 Using high-quality, 75 ohm BNC cables (not in-
cluded) connect the Mbox Pro Word Clock In
and Out connectors to the appropriate ports on
the other Word clock-capable devices in your
studio.
Using Word Clock with Pro Tools
Pro Tools with Mbox Pro can act as Word clock
master, or as a slave to Word clock supplied by an
external device.
Pro Tools as Word Clock Master
Mbox Pro Word clock output is always active, let-
ting Pro Tools supply Word clock to any con-
nected devices that support standard Word clock.
To use Pro Tools as Word clock master:
1 Make sure all connections are correct between
Mbox Pro and your external devices.
2 Configure all external devices to slave to the
Word clock coming from Mbox Pro. (Be sure to
verify sample rate settings, termination require-
ments and other internal settings for the device;
refer to the manufacturer’s documentation if
you need more information on the particular re-
quirements for your other equipment.)
3 Launch Pro Tools.
4 Choose Hardware > Setup.
5 Click the Clock Source pop-up menu and
choose
Internal.
Pro Tools as Word Clock Slave
In order to slave Pro Tools to an external Word
clock source, you must configure Word clock as
the Pro Tools Clock source.
To configure Pro Tools with Mbox Pro as a Word
clock slave:
1 Make sure all Word clock and audio connec-
tions are correct as described earlier in this sec-
tion.
2 Make sure the external Word clock source is
powered on, and configured to output 1x Word
clock. (Be sure to verify any required termina-
tion; refer to the manufacturer’s documentation
if you need more information on the particular
requirements for your device.)
3 Launch Pro Tools.
Do not confuse Word clock and other forms
of “clock reference” with time code and
other forms of “positional reference.” For an
overview of synchronization terminology and
concepts, see the
Pro Tools Reference guide.
Mbox Pro can synchronize to Word clock at
44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4
kHz, and 192 kHz sample rates.
When using third-party applications, you can
configure the Clock Source for Mbox Pro us-
ing the Control Panel. See “Clock Source”
on page 27.