Mackie HDR 24/96 How can you Sync to Word Clock and Time Code at the Same Time

HD24/96 Technical Reference 92

Sample Clocks of both units are locked to each other, it doesn’t matter which unit generates time code. The example below shows a different way of setting up two HDR24/96 units that is also correct. In this example the machine on the left generates word clock and locks to time code, and the machine on the right locks to word clock and generates time code.

Time Code

	Word Clock
Clock Master /	Clock Slave /
Time Code Slave	Time Code Master

Word clock can also come from an external source like a word clock generator, a digital console, A/D converter, or DAW. As long as all devices lock to the same sample clock, it really doesn’t matter who generates the clock. The example below illustrates this.

Word Clock Generator

Time Code

Clock Slave /	Clock Slave /
Time Code Master	Time Code Slave

Which method you use is completely dependent on your setup.

How can you Sync to Word Clock and Time Code at the Same Time?

This is a good question, and one that often causes confusion. The following example best illustrates the answer.

Time Code

Master HDR24/96 Slave HDR24/96

In the example above, the slave receives time code but not word clock from the master. When you press play on the master, the slave precisely locks its transport position to the master’s position. However, once the slave HDR24/96 locks to time code from the master, it effectively “ignores” time code from the master and plays back audio at the Sample Rate generated by its internal Sample Clock. Because the clocks of the two units are not synchronized, the audio and the time displays between the two units will drift over time. This example is exactly analogous to the problem of trying to synchronize two wristwatches to each other.