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Appendices...
4. External Clock Input – Unit Differences
The way in which ISA One responds to an external clock selection will vary slightly depending on the
unit’s revision.
On earlier units, the EXT clock input selections will include a 256X setting rather than the Dante
Clock setting used on later units.
Front Panels Marked “256X”
The front panel EXT LED indicators will only follow the rate selected if the change is made using the
front panel switch.
If a change to the external clock is made over the network, the front panel LED won’t update, and the
LOCK LED will start flashing.
Note that the unit will still operate correctly – it will still follow the RNC2 or the front panel switch selection – but
it won’t have updated the front panel LED indication.
When a change is made from the front panel, the unit will always toggle to whichever would be the
next selection. For example: if the front panel is set to 48k, and the setting is changed to 44.1k via
RNC2, 88.2k will still be the next sample rate selected by pressing the button on the front panel. This
behaviour is the same for the sync source.
Front Panels Marked “Dante Clock”
On newer units the EXT LEDs will always indicate the correct setting whether changes are made
from the front panel or via the network.
