Orban OPTIMOD 8685, Operating Manual

Page: 61 / 357

OPTIMOD SURROUND PROCESSOR INSTALLATION
2-7
HD-SDI Input and Output (optional)
The optional HD-SDI input/output supports SD-SDI (per SMPTE 259M); 1.5 Gbit/s HD-
SDI (per SMPTE 292M; up to 720p and 1080i) and 3.0 Gbit/s single-wire HD-SDI (per
SMPTE 424M; 1080p). Only audio channels 1 through 8 are supported; these can be
routed to and from several destinations (see
Table 2-2: Routing Switcher Sources and
Destinations on page 2-23). See Optional HD-SDI Input/Output Interface Module on
page 6-3 for a detailed specification.
The HD-SDI input/output has a hard-wire relay bypass that connects the input BNC
connector directly to the output BNC connector automatically when no power is
connected to the 8685 and if several classes of faults occur in the 8685’s circuitry.
Wordclock/AES11id Sync Input
The sync input accepts a standard 5V p-p squarewave 1 x word clock signal (a
squarewave at the sampling frequency) or an AES11id signal, automatically de-
tected. A menu item allows you to synchronize the output sample frequency to the
frequency present at the sync. The connector is a female BNC with the shell
grounded to chassis.
To permit daisy-chaining sync signals, the input impedance is greater than 1 K
Ω
. If
the 8685 is the last device driven by the sync coaxial cable, you should terminate it
by using a BNC Tee connector and a 75
Ω
BNC terminator. This will prevent perform-
ance-degrading reflections in the cable. This is required for both word clock and
AES11id operation.
Analog Audio Output
•
We recommend using two-conductor foil-shielded cable (like Belden 8451 or
equivalent) for the analog output connections because signal current flows
through the two conductors only. The shield does not carry signal and is used
only for shielding.
•
Analog output connectors are XLR-type connectors. There are two connectors.
These are intended for monitoring and troubleshooting. You can specify which
signals (LF, RF, C, LS, RS, LFE, LB, RB, STEREO L, STEREO R, DOWNMIX L,
DOWNMIX R, LF/RF, C, LS/RS, LB/RB, STEREO, or DOWNMIX) drive these outputs.
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 pin 2 or 3 is considered LOW, the other pin
is automatically HIGH.
•
Electronically balanced and floating outputs simulate a true transformer output.
The source impedance is 50
Ω
. The output is capable of driving loads of 600
Ω
or
higher; the 100% modulation level is adjustable with the AO 100% control over
a –6dBu to +24dBu range. The outputs are EMI suppressed.