Operation; Selecting The Aes/Ebu Clock Source - Alesis adat AI4 Reference Manual

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Operation

Operation of the AI4 is extremely direct and straightforward. All the
action starts—and ends—with the two Clock Source Select buttons.
Press each button to cycle through the available clock sources at the
respective AES/EBU and ADAT Optical inputs. The corresponding
LEDs let you know which input is selected as the clock master, while the
sample rate LEDs automatically indicate the incoming sample rate.
The AI4 routes and converts digital signal and digital clocks, but it isn't in
itself a clock master. You must designate one device in your system as
the master clock. The clock master can come from:
• Any of the AES/EBU inputs
• The ADAT Optical input
• The Word Clock input
Follow the manufacturer's instructions to set the clock status of the
devices in your system. The master clock source can be connected to the
AES/EBU, Word Clock, or ADAT Optical inputs.

Selecting the AES/EBU Clock Source

The AI4's AES/EBU section can accept master clock from inputs 1/2,
3/4, 5/6, 7/8, or from the Word Clock input.
The front panel CLOCK SOURCE SELECT button toggles through
these choices, lighting the CLOCK SOURCE LEDs to indicate which
input is the active clock master.
When the selected input is receiving a valid clock, the CLOCK SOURCE
LED will light green. If no valid clock source is present at the selected
input, the LED will flash, and the outputs will be muted.
The SAMPLE RATE LED indicates the detected incoming nominal
sample rate. If the actual sample rate is more than 2% different from the
nearest nominal, the LED representing the closest match will flash.
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