8
I
nput connectors
The SDA 2175 has input sockets for both balanced and unbalanced signals, but only one may
be used at a time. The XLR and phono sockets are internally connected in parallel, so only
one set of the connectors should be connected externally.
ALWAYS
use
EITHER
the XLR
inputs
OR
the phono inputs.
NEVER
use both at the same time.
Fig 3: SDA 2175 Input configuration.
Balanced inputs
The balanced XLR inputs are wired in accordance with IEC268:
Pin 1: Chassis and ground.
Pin 2: Hot (+).
Pin 3: Cold (-).
Shell: Chassis and ground.
When the balanced inputs are used with a balanced source, the input selector switch
MUST
be set to the BALANCED position. The switch position can be changed with a small
screwdriver.
If any cables are connected to the unbalanced inputs, remove these
before the switch is put in the BALANCED position.
We recommend the use of the balanced inputs whenever possible, as balanced signals are
much less sensitive to noise than unbalanced signals.
