MACKIE Digital 8Bus D8B v5.1 - Manual (Page 124)

D8B Manual • Chapter 4 • page 118
Verifying Word Clock Sync Between Devices
and the Digital 8•Bus
• When the D8B is set to “Internal” in the Apogee
Clock pop-up window, it generates word clock as
a master device. All other devices must be
connected as slaves.
• If the D8B is slaved properly to a master word
clock source, “Locked.” is displayed in the
Setup>Digital I/O window next to the Apogee
Clock pop-up window and an asterisk (*) flashes in
the right-most portion of the control surface VFD.
• If the D8B is improperly connected as a slave to
the digital network, “Lock Error.” is displayed in
the Setup>Digital I/O window next to the Apogee
Clock pop-up window and a question mark (?)
flashes in the right-most portion of the control
surface VFD.
You probably have a bad word clock sync
connection if:
• You hear audio but it cuts in and out at regular
intervals.
• There is no audio signal at the input of the D8B
even though everything seems to be connected
properly.
• All meters are full on and you hear a very ugly
grating, grinding, static sound.
• When the record/playback device transport is
engaged, you see a question mark flashing in the
right-most portion of the control surface VFD.
Troubleshooting Word Clock Problems
• Troubleshoot through the system from the master
through the slaves. Connect the first two devices
and verify their functionality. Once they’re up and
running, add the next device, and so on. This is
the most efficient manner to check out a system.
• Verify connection, integrity, and quality of all sync
cables.
• Verify a consistent sample rate setting on all
connected sync devices (all set to the same
sample rate—44.1, 48k, etc.)
• Verify that the master sync source word clock
output is connected to the word clock input of the
slave, and that additional slaves also receive word
clock. Slaves can either receive word clock
directly from the master device or daisy-chained
through connected slaves. Patch word clock out of
a connected slave into the word clock input of any
other slave.
• Verify that the master device word clock status is
set to INTERNAL.
• Verify that all slave devices are set to follow
EXTERNAL word clock.
• If the system doesn’t seem to work correctly, you
might have an intermittent or broken sync cable.
Always use high-quality 75
Ω BNC word clock
cables.