206 Chapter 16—Using the Digital Inputs & Outputs

About Wordclocks

Unlike analog audio equipment, digital audio equipment must be synchronized when digital audio is transferred from one device to another. Otherwise, the digital audio might not be read correctly and audible noise, glitches, or clicks may occur. Synchroni- zation is achieved using what’s called a wordclock, which is a clock signal for synchro- nizing all the digital audio words in an audio system. Note that wordclocks are not the same as SMPTE or MIDI timecode, which are used to synchronize audio recorders, MIDI sequencers, and so on. Wordclock synchronization refers to the synchronization of the digital audio processing circuits inside each digital audio device.

In a typical digital audio system, one device acts as the wordclock master and the other devices act as wordclock slaves that synchronize to the master wordclock signal. If the 01V is the only digital audio device in your system, no special wordclock settings are required and the 01V synchronizes to its own internal wordclock. Add a DAT recorder or digital multitrack recorder, however, and you must decide which device to use as wordclock master and which devices to use as slaves. Even when you’ve done this and configured your system, it may be necessary to change the wordclock settings in certain situations, such as when recording from a DAT or CD player.

The wordclock signal runs at the same frequency as the sampling rate. The 01V gener- ates its own wordclock at 44.1 kHz (the industry-standard sampling rate for music CDs) and can be used as wordclock master. Alternatively, it can be used as a wordclock slave synchronized to an external wordclock of between 44.1 kHz –10% and 48 kHz +6%. Converting the sampling rate of digital audio is a complicated process, so it’s best to use the 44.1 kHz sampling rate, especially if your work is destined for CD distribu- tion.

Wordclock signals can be distributed via dedicated cables or derived from standard dig- ital audio connections, as shown below. With AES/EBU and Coaxial digital audio con- nections, a wordclock signal is transmitted even when no audio signal is present.

Wordclock slave

 

 

 

 

 

 

Wordclock slave

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Wordclock In

Wordclock Out

Digital Audio Out

Digital Audio In

00.00.00.00DAT

Wordclock

master

Digital Audio In

Digital Audio Out

Wordclock Out

Wordclock In

00.00.00.00

 

 

DAT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Wordclock slave

Wordclock slave

In a system where all devices share a common wordclock, it’s important that all devices be turned on even when they’re not being used. Turn on the wordclock master first, and then the slaves. When shutting down the system, turn off the slaves first, and then the master. Before commencing with a recording session, make sure that all wordclock slaves are synchronized to the master wordclock. Some devices have front panel indica- tors to show when they are wordclock synchronized. Refer to the instructions for each device.

The following system examples show three typical wordclock setups with the 01V. For detailed system examples with specific equipment, see “System Examples” on page 241.

01V—Owner’s Manual

Page 216
Image 216
Yamaha 01v owner manual About Wordclocks