Orban OPTIMOD 8685, Руководство по эксплуатации

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TECHNICAL DATA ORBAN MODEL 8685
Delay: The minimum available input/output delay is approximately 20 ms with look-ahead
limiting active and 6 ms with look-ahead limiting bypassed. This can be padded to ex-
actly one or two frames of 24, 25, 29.97, 30, 50, 59.94, or 60 frames/second video up to
a maximum delay of 60 ms. (Two frames are required for 59.94/60 fps progressively
scanned video.) The optional HD-SDI I/O module provides video delay of up to 11
frames to compensate for the delay of the 8685’s loudness processing (approximately
one frame), optinal Penteo® upmixer (approximately seven frames) and optional Dolby-
E® decoder and encoders (one frame apiece).
Surround Processing Stereo Coupling: All channels of the AGC and compressors are
coupled using r.m.s. summation. The user can select whether or not the LFE channel
contributes to the r.m.s. sum in the AGC and compressor control sidechains. Peak limit-
ers in the multiband compressor limiter and look-ahead limiters all operate uncoupled to
prevent transients in a given channel from causing audible loudness modulation in other
channels. In additional, the compressors acting on the center channel can be uncoupled
from the remaining channels within a user-selectable window, allowing the processing to
correct the balance between dialog and remaining program elements automatically.
2.0 Processing Stereo Coupling: Stereo or dual-mono. In dual-mono mode, both process-
ing channels have the same subjective adjustments (as determined by the active preset)
but are otherwise independent, making this mode appropriate for dual-language trans-
missions. In stereo mode, the user can set the maximum permitted gain difference be-
tween the channels in each band of the multiband compressor/limiter. 2.0 Stereo/Dual-
Mono operating mode can be set via GPI, Ethernet and serial connections, internal
clock-based automation, and AES3 Status Bits.
Loudness Level Meter (x2): One meter for the surround processing and one meter that
can be switched to indicate the output loudness of any of the four 2.0 processing chan-
nels, both meters realized in software. There are two meters that operate simultane-
ously: one meter displays loudness using the EBU R-128 algorithm (which is based on
ITU-R BS.1770 algorithm, but with silence gating). The other meter uses the Jones &
Troick algorithm developed at CBS Technology Center in 1981. The two meters can be
displayed on the 8685’s front-panel screen and on its PC Remote software.
In ITU terminology, the Jones & Torick meter measures “short-term” loudness. Its dis-
play time constants are matched to the loudness integration time of the human ear,
reaching steady-state level in approximately 200 ms and having a decay time constant
of approximately 300 ms. (B. L. Jones & E. L. Torick: “A New Loudness Indicator for Use
in Broadcasting,” J. SMPTE, September 1981, pp 772-777.)
Installation
Base Configuration: Digital Audio Inputs (x5)
Configuration: Each of five hardware inputs accepts two audio channels per AES3id stan-
dard, 24 bit resolution. Internal programmable routing switcher allows any of the 10
physical input channels to be routed to the LF, RF, C, LB1, RB1, LFE, LB2, RB2,
STEREO L, or STEREO R inputs of the audio processing. For the 2.0 processing, unit
can detect Stereo or Two-Channel status bits appearing at Input #1 and switch the 2.0
processor between stereo and dual-mono modes.
User Bits: Unit can pass AES3id User Bits from Input #1 to Output #1.
Sampling Rate: 32, 44.1, 48, 88.2, or 96 kHz, automatically selected.
Connector: BNC, female, shell bypassed to chassis via 1000 pF capacitor, EMI-
suppressed. 75
Ω
impedance, terminated.
Input Reference Level : Variable from –30 dBfs to –10 dBfs.