MOTU 896 User's Guide download pdf (Page 30)

INSTALLING THE 896MK3 HARDWARE

SYNCING OPTICAL DEVICES

When connecting an optical device, make sure that

its digital audio clock is phase-locked (in sync

with) the 896mk3, as explained in “Making sync

connections” on page 28. There are two ways to do

this:

1. Resolve the optical device to the 896mk3

2. Resolve the 896mk3 to the optical device

For 1), choose Internal (or any other clock source

except ADAT optical) as the clock source for the

896mk3 in MOTU Audio Setup.

For 2), choose either ADAT Optical A or ADAT

Optical B as the 896mk3’s clock source

(Figure 4-12). Be sure to choose the optical port

that the device is connected to.

Figure 4-12: Resolving the 896mk3 to an optical device.

For details about using the clock source setting and

the MOTU Audio Setup software in general, see

chapter 5, “MOTU Audio Setup” (page 41).

Using word clock to resolve optical devices

If the optical device you are connecting to the

896mk3 has word clock connectors on it, you can

use them to resolve the device to the 896mk3,

similar to the diagram shown in Figure 4-11 on

page 29 for S/PDIF devices with word clock. Also

see “Syncing word clock devices” on page 33.

SYNCING AES/EBU DEVICES

If you would like to transfer stereo audio digitally

between the 896mk3 and another device that has

AES/EBU, connect it to the 896mk3’s AES/EBU

jacks with balanced, AES/EBU grade audio cables.

AES/EBU clock and sample rate conversion

The 896mk3 AES/EBU section is equipped with a

real-time sample rate converter that can be used for

either input or output. This feature provides a great

deal of ﬂexibility in making digital transfers. For

example, you can:

■ Transfer digital audio into the 896mk3 at a

sample rate that is completely different than the

896mk3 system clock rate.

■ Transfer digital audio into the 896mk3 without

the need for any external synchronization

arrangements.

■ Transfer digital audio out of the 896mk3 at

double or half the 896mk3 system clock rate.

Rate conversion does not add any appreciable noise

to the audio signal (under -120 dB).

Digital audio phase lock

Without sample rate conversion, when you transfer

digital audio between two devices, their audio

clocks must be in phase with one another — or

phase-locked — as discussed earlier in “Be sure to

choose a digital audio clock master” on page 28

and Figure 4-10 on page 28. Otherwise, you’ll hear

clicks, pops, and distortion in the audio, or

perhaps no audio at all. Phase lock ensures a clean

digital audio transfer.

Another beneﬁt of direct master/slave clocking

(without sample rate conversion) is that each

slaved device remains continuously resolved to the

master, which means that there will be no gradual

drift over time. This form of synchronization is

best for audio that needs to remain resolved to ﬁlm,

video, etc.

896mk3 Hybrid book Page 30 Friday, August 19, 2011 1:44 PM

1 2 ... 25 26 27 28 29 30 31 32 33 34 35 ... 133 134

Comments to this Manuals

No comments

MOTU 896 User's Guide Page 30

Comments to this Manuals

Related products and manuals for Recording Equipment MOTU 896