d&b D80 - Manual (Page 34)

9.2. Input
Selecting the «Input» tab allows you to configure the Input mode
for the input connector pairs 1/2 and 3/4 independently to accept
either analog or digital input signals.
The operating mode of the corresponding link output connectors 2
and 4 depends on the set input mode.
9.2.1. Input mode
Input mode block diagram
Analog/Analog
Both input connector pairs ½ and 3/4 are set to «Analog», an
analog audio signal is accepted by inputs 1, 2, 3 and 4.
d&b D80 Manual 1.9 en 34