Yamaha A3000 Owner's Manual page 17

A3000 Options
The I/O Expansion Board (AIEB1 Board)
In its standard configuration, the A3000 supports analog I/O only. Although it stores all
internal data in digital form, it does not provide direct digital I/O connectors.
You can add digital I/O capacity by installing an AIEB1 board. The board offers two
different digital connector types: optical connectors, and coaxial connectors. As an added
benefit, the board also includes three stereo ASSIGNABLE OUTPUT pairs (six analog
jacks), which operate independently of the standard STEREO OUT and ASSIGNABLE
OUT jacks.
For information about how to install this board, refer to the Appendix. ( 312)
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