Syncing S/Pdif Devices; Syncing Optical Devices - MOTU 828 User Manual

Also remember that audio phase lock can be
achieved independently of timecode (location).
For example, one device can be the timecode
master while another is the audio clock master, but
only one device can be the audio clock master. If
you set things up with this rule in mind, you'll
have trouble-free audio transfers with your
MOTU hardware.

SYNCING S/PDIF DEVICES

The 828 provides RCA S/PDIF digital input and
output. Your 828 and the other S/PDIF device will
sync to each other by way of the S/PDIF
connection itself for click-free digital transfers.
One device is the master, and the other device is
the slave.
Syncing the 828 to its S/PDIF input
When you transfer audio from the S/PDIF device
into the 828, choose S/PDIF as the clock source
(item #3 on page 43) to resolve the 828 to its
S/PDIF input, as shown in Figure 4-10.
828
S/PDIF device
828
Clock Source setting =
S/PDIF (when transferring from the
other device to the 828)
Figure 4-10: The setup for synchronizing a S/PDIF device with the 828.
Sync is achieved via the digital I/O connection itself.
30
S/PDIF
S/PDIF
828
Clock Source setting =
Internal (when transferring from the
828 to the other device)
Syncing another S/PDIF device to the 828
When transferring audio from the 828 to another
S/PDIF device, set the 828 clock mode (item #3 on
page 43) to any source other than S/PDIF. Doing
so makes the 828 the clock master. When the other
device records (or receives) S/PDIF audio (from
the 828), it will simply synchronize to the clock
provided by the 828 S/PDIF signal.

SYNCING OPTICAL DEVICES

There are several ways to sync an optical device
with the 828:
A. Resolve the other device to the 828
B. Resolve the 828 to the other device
C. Resolve both devices to a word clock source
For A, choose Internal as the clock mode in the
Device tab (item #3 on page 43). Then configure
the other device to resolve to its optical input.
Alternately, the MOTU interface could be resolved
to any other external clock source besides Optical.
For B, choose Optical as the clock mode (item #3
on page 43), and configure the other device to
resolve to its own internal clock.
For C, choose Word Clock as the clock mode for
the 828 (item #3 on page 43), and resolve the other
device to its word clock input.
Using word clock to resolve optical devices
If the optical device has word clock connectors on
it, you can use them to synchronize the device
with the 828. See the next section, "Syncing word
clock devices".
H A R D W A R E I N S T A L L A T I O N