User`s guide

MOTU FIREWIRE CONTROL PANEL (MAC OS 9)
47
are doing is playing tracks off hard disk in your
digital audio software on the computer. In a
situation like this, you most often don’t need to
reference an external clock of any kind.
Another example is transferring a mix to DAT. You
can operate the 896HD system on its internal
clock, and then slave the DAT deck to the 896HD
via the AES/EBU connection (usually DAT decks
slave to their AES/EBU input when you choose the
AES/EBU input as their record source) or via the
896HD’s word clock output (if your DAT deck has
a word clock input).
If you would like help determining if this is the
proper clock setting for your situation, see “Do you
need a synchronizer?” on page 20.
With ADAT devices, however, you usually want an
external digital audio synchronizer, such as the
MIDI Timepiece AV or Digital Timepiece, to be the
digital clock master. In this case, you would set the
896HD clock source setting to ADAT 9-pin, as
described below.
AES/EBU
The AES/EBU clock source setting refers to the
AES/EBU input connector on the 896HD. This
setting allows the MOTU 896HD to slave to
another AES/EBU device.
Use this setting whenever you are recording input
from a DAT deck or other AES/EBU device into the
896HD. It is not necessary in the opposite direction
(when you are transferring from the 896HD to the
DAT machine).
For further details about this setting, see “Syncing
AES/EBU devices” on page 26.
Wor d C l o ck I n
The Word C lo c k In setting refers to the Word Clock
In BNC connector on the 896HD rear panel.
Choosing this setting allows the 896HD to slave to
an external word clock source, such as the word
clock output from a digital mixer or another
MOTU FireWire interface.
ADAT 9-pin
The ADAT 9-pin clock source setting refers to the
ADAT digital audio synchronization format. It
allows the 896HD to slave to an ADAT — or ADAT
sync chain — via its ADAT sync 9-pin connector.
ADAT sync also carries precise, sample location
information, which allows AudioDesk and Digital
Performer to transfer audio to and from ADATs
without drifting by as much as one sample.
Use this setting when you are using the 896HD
with one or more ADATs. Make sure the 896HD is
connected to the end of the ADAT sync chain.
Yo u s h o u l d also use this setting if you have a MIDI
Timepiece AV, which allows you to drive your
entire system from the transport controls of
AudioDesk, Digital Performer or other software.
Yo u c o u l d also use ADAT sync to continuously
resolve the 896HD to SMPTE time code, video,
and word clock via a synchronizer like the MOTU
MIDI Timepiece AV. Word clock can accomplish
the same thing.
For further details, see “Sample-accurate ADAT
sync” on page 22, “Sample-accurate ADAT sync
with no synchronizer” on page 23 and “Syncing to
video and/or SMPTE time code” on page 24.
ADAT optical
The ADAT optical clock source setting refers to the
clock provided by the 896HD’s optical input, when
it is connected to an ADAT optical device. This
setting can be used to slave the 896HD directly to
the optical input connection. Most of the time, you
can set up a better operating scenario that uses one
of the other synchronization options. However,
there may be occasions when you have an ADAT
optical compatible device that has no way of