Orban Optimod-PC 1101, Operating Manual

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OPTIMOD-PC INSTALLATION
2-17
Analog Input and Output Audio Connections
Cable
We recommend using two-conductor foil-shielded cable (such as Belden
8451/1503A/1504A/1508A or equivalent for analog signals and Belden 1800B/1801B
or equivalent for digital signals), because signal current flows through the two con-
ductors only. The shield does not carry signal, and is used only for shielding.
Connectors
The cable assemblies are optional and must be purchased separately from OPTIMOD-
PC. Input and output connectors are XLR except for the sync input, which is BNC fe-
male.
In the XLR-type connectors, pin 1 is CHASSIS GROUND, while pin 2 and
pin 3 are a balanced, floating pair. This wiring scheme is compatible with
any studio-wiring standard: If one pin is considered LOW, the other pin is
automatically HIGH. However, we arbitrarily call pin 2 HIGH and pin 3
LOW to conform to AES standards.
See Figure 2-2: Wiring Diagram for the 1101 OPTIMOD-PC XLR on page
2-5.
Analog Audio Input
Using Orban’s mixer application (available from the T
OOLS
menu on the Orban Con-
trol application or from your computer’s control panel in Multimedia), you can
choose a nominal input level of either –10dBV (IHF consumer level) or +4dBu (pro-
fessional level).
(0dBu = 0.775Vrms. For this application, the dBm@600
Ω
scale on voltme-
ters can be read as if it were calibrated in dBu. 0dBV = 1.0Vrms.)
The peak input level that causes overload depends on whether you have set the in-
put for –10 dBV (–7.8 dBu) or +4dBu. Overload occurs at approxi9.2 dBV
(+11.4 dBu) for the –10 dBV setting and +24 dBu for the +4 dBu setting.
The electronically balanced input uses an ultra low noise and distortion differential
amplifier for best common mode rejection. It is compatible with most professional
and semi-professional audio equipment, balanced or unbalanced, having a source
impedance of 600
Ω
or less. The input is EMI suppressed.
•
Input connections are the same whether the driving source is balanced or unbal-
anced.
•
Connect the red (or white) wire to the pin on the XLR-type connector (#2 or #3)
that is considered HIGH by the standards of your organization. Connect the
black wire to the pin on the XLR-type connector (#3 or #2) that is considered
LOW by the standards of your organization.