MOTU Traveler-mk3 User Manual page 27

Do you need to synchronize the Traveler-mk3?
If you will be using only the Traveler-mk3's analog
inputs and outputs (and none of its digital I/O),
and you have no plans to synchronize your
Traveler-mk3 system to SMPTE time code, you
don't need to make any sync connections. You can
skip this section and proceed to chapter 4,
"Installing the Traveler-mk3 Mac Software"
(page 33). After you install the Traveler-mk3
software, you'll open MOTU Audio Setup to
confirm that the Clock Source setting is Internal as
shown below. For details, see chapter 5, "MOTU
Audio Setup" (page 37).
Figure 3-14: You can run the Traveler-mk3 under its own internal
clock when it has no digital audio connections and you are not
synchronizing the Traveler-mk3 system to an external time reference
such as time code.
Situations that require synchronization
There are three general cases in which you will
need to resolve the Traveler-mk3 with other
devices:
Synchronizing the Traveler-mk3 with other
■
digital audio devices so that their digital audio
clocks are phase-locked (as shown in Figure 3-15)
Resolving the Traveler-mk3 system to SMPTE
■
time code from a video deck, analog multi-track,
etc.
Both of the above
■
Synchronization is critical for clean digital I/O
Synchronization is critical in any audio system, but
it is especially important when you are transferring
audio between digital audio devices. Your success
in using the Traveler-mk3's digital I/O features
I N S T A L L I N G T H E T R A V E L E R - M K 3 H A R D W A R E
depends almost entirely on proper synchroni-
zation. The following sections guide you through
several recommended scenarios.
Be sure to choose a digital audio clock master
When you transfer digital audio between two
devices, their audio clocks must be in phase with
one another — or phase-locked. Otherwise, you'll
hear clicks, pops, and distortion in the audio — or
perhaps no audio at all.
Not phase-locked
Device A
Device B
Figure 3-15: When transferring audio, two devices must have phase-
locked audio clocks to prevent clicks, pops or other artifacts.
There are two ways to achieve phase lock: slave one
device to the other, or slave both devices to a third
master clock. If you have three or more digital
audio devices, you need to slave them all to a single
master audio clock.
Master
Slave Slave
Figure 3-16: To keep the Traveler-mk3 phased-locked with other
digital audio devices connected to it, choose a clock master.
Also remember that audio phase lock can be
achieved independently of time code (location).
For example, one device can be the time code
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 the Traveler-mk3.
Phase-locked
Master
Slave
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