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internal ground from the mains earth, just in case
there should be any hum problems occuring due
to different potentials between the connected
units.
Signal connections
The signal connections are located in the centre
of the rear panel, directly under the large
heatsink, please see Fig. 2.2/2 and read the
following description:
Analog Input:
Analog signal sources will be connected to
this XLR socket. Via the selection switch „
In-
put Section
“ the input stage of the O 500 C
can be selected for the electronically balanced
format, or a transformer balanced input stage.
Although the transformer is of very high
quality, the position „electronically balanced“
should be preferred for best signal quality.
Only in case of hum problems or special
installations, where transformer isolation is a
must, the transformer balanced position
should be chosen.
Serial Port:
This connector (SUB-D 25 Pin) has several
functions:
It contains the serial RS-232 ports, which are
Fig. 2.2/2: The signal connectors in the middle of the rear panel of O 500 C
needed to connect an external PC for
downloading the presets into the O 500 C.
In combination with this, a complete MIDI
interface (In, Out, Through) is provided in this
connector, so that several O 500 C monitors
can be interconnected to eachother.
Chapter 4 shows the complete wiring scheme
of this connector and gives a description of
the connecting cables needed.
Reset:
The RESET key is used to restart the internal
digital controller without switching OFF the
system as it is the case with mains ON / OFF.
Digital S/P-DIF Input:
This BNC socket is connected to incoming S-
PDIF audio signals. The selection of the signal
source is described in chapter 3.2. When
using this BNC input for digital audio signals,
make sure that no connection is made to the
AES/EBU input!
Digital AES/EBU Input:
Incoming digital signals in the AES/EBU
format are connected to this XLR socket.
When this input is used for digital audio
signals, please make sure that no connection
is made to the BNC socket!
RESET
ANALOG INPUT
SERIAL PORT
DIGITAL S/P-DIF
INPUT
DIGITAL AES/EBU
INPUT
THROUGH
SUBWOOFER
transformer
balanced
RS 232 IN
MIDI IN / MIDI OUT
electr.
balanced
INPUT
SECTION
PIN 1 =
PIN 2 =
PIN 3 =
+
-
Choose electronically
balanced input for
optimized performance
PIN 1 =
PIN 2 =
PIN 3 =
Input for Analog
Sources
Selector for Transformer or Electronic
Symmetric Mode of Analog Input
Input for Digital
AES/EBU Sources
Output for Digital
AES/EBU Signals
Analog Output for
Optional Subwoofer
Interface
(RS-232, MIDI, Memory Modul)
Input for Digital
S/PDIF Sources
Digital Controller
Reset Button
