Hdr 24/96 – MACKIE HDR24/96 User Manual
Page 197
HDR 24/96
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.
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.
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.
Video / Word Clock
Generator
Video Slave
Video Slave
Video Slave
Blackburst
Blackburst
Blackburst
VTR
Digital Audio
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 provide the timing
accuracy necessary to insure that digital audio signals are received within the acceptable time
window.
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 provide the timing
accuracy necessary to insure that digital audio signals are received within the acceptable time
window.
The picture below illustrates the relationship between the sample clocks of two digital audio devices
locked to a common word clock signal (left) and a common video signal (right).
The picture below illustrates the relationship between the sample clocks of two digital audio devices
locked to a common word clock signal (left) and a common video signal (right).
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