User`s guide

INSTALLING THE PCI-424 HARDWARE
36
Figure 4-13: Click the ‘Interface Options’ button in the MOTU PCI
Audio Console window to access the AES/EBU output clock options.
System
To make the AES/EBU output sample rate match
the System sample rate, choose System. No
additional connections are necessary. And no
sample rate conversion occurs when this setting is
chosen.
AES Input
To make the AES/EBU output sample rate match
the sample rate currently being received by the
HD192’s AES/EBU input, choose AES Input. This
setting requires a connection to the HD192’s AES/
EBU input from a device that is transmitting an
AES/EBU clock signal.
☛ Be careful when both the HD192’s AES/EBU
input and output are connected to the same
external device: this option is likely to create a
clock loop.
AES Word In
If you have an external word clock source, and you
would like the HD192 AES/EBU output to resolve
to it, connect the word clock source to the ‘HD192
AES Word In’ as shown below in Figure 4-14. Then,
choose AES Word In from the AES Output Clock
menu (Figure 4-13 above).
Figure 4-14: Resolving the AES/EBU output to its own independent
word clock.
44.1 / 48 / 88.2 / 96 kHz
Choose one of these sample rates when the desired
AES/EBU output rate needs to be different than the
HD192 system clock rate. When you choose one of
these rates, an additional option appears called
Fixed Frequency, which lets you resolve the AES/EU
output rate to the HD192 system clock. In either
case, sample rate conversion occurs if the sample
rate you’ve chosen is different than the HD192
system clock rate. For further details about this
option, see “HD192 interface options” on page 71.
This BNC connector lets you
resolve the HD192 AES/EBU
output to a word clock source
that is different than the
system word clock input.