MACKIE HDR 24/96 - Manual (Page 97)

HD24/96 Technical Reference 97
An example of how two HDRs can be synchronized to a VTR using video is shown below:
In this setup each of the three devices is a video slave to the master video generator. This
setup works well when digital audio is signals are NOT connected between the digital audio
devices, but will not work when the digital audio signals are connected between the devices.
The setup shown below illustrates this very common mistake.
When digital audio signals are connected between digital audio devices it is imperative that
their clocks be synchronized to a common word clock source, regardless of whether or not
video synchronization is involved.
Digital audio devices expect to receive digital audio signals within a certain “window” of time
relative to the start of the word clock signal. If it receives them outside the time window, the
data may not be read properly and you get a “pop” in your audio. Video signals do not
V i d e o / W o r d C l o c k
G e n e r a t o r
Video Slave
Video Slave Video Slave
Blackburst Blackburst
Blackburst
V T R
Video / Word Clock
Generator
Video Slave
Video Slave Video Slave
Blackburst Blackburst
Blackburst
V T R
Digital Audio