Orban OPTIMOD-FM 8600, Operating Manual

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INTRODUCTION ORBAN MODEL 8600
Thanks to true peak control, sample rate conversion , unless it removes high
frequency program energy or introduces group delay distortion,
cannot cause
sample peaks to increase more than 0.5 dB . For example, sample rate con-
version from 48 kHz to 44.1 kHz is highly unlikely to cause sample peak clipping
in the 44.1 kHz audio data.
Flexible Configuration
•
OPTIMOD-FM 8600 is supplied with analog and AES3 digital inputs and out-
puts . The digital input and the two digital outputs are equipped with sample-
rate converters and can operate at 32 kHz, 44.1 kHz, 48 kHz, 88.1 kHz, and 96
kHz sample rates. The preemphasis status and output levels are separately
adjustable for the analog and digital outputs. Each output can emit the analog
FM processed signal, the analog FM processed signal with diversity delay ap-
plied, the digital radio processed signal, or the low-delay monitor signal.
•
A loop-through connection is provided to enable a ratings encoder (such as
Nielsen Audio ®) to be embedded in the audio processing. (See Connecting a
Ratings Encoder on page 2-8.)
•
The 8600 has two independent equalizers, multiband compressors, and
peak limiters for the FM analog and digital media processing channels ,
allowing you to separately optimize the processing for each.
•
An AES11 sync input allows you to synchronize the output sample rate of ei-
ther (or both) AES3 outputs to this input. You can also synchronize the out-
puts to the AES3 digital input or to 8600’s internal clock . The sync source
of each AES3 output is independently selectable.
•
A defeatable diversity delay can delay the FM analog processing output up to
16.2 seconds . Delay can be trimmed in intervals of one sample of 64 kHz to
match the analog and digital paths in the HD Radio system, eliminating the
need to use the delay built into the HD Radio exciter and permitting the
8600’s internal stereo encoder and composite limiter to drive the analog
FM exciter
. Both the 8600 and 8600FM offer this feature, making it convenient
to use the 8600FM in dual-processor HD installations where the digital channel
receives independent processing from a processor like Orban’s Optimod-DAB or
Optimod-PC. Each output (Analog, Digital 1, Digital 2, Composite) can be
inde-
pendently configured to emit the delayed or undelayed signal .
•
Built-in RDS/RBDS generator.
•
The analog inputs are
transformerless, balanced 10k Ω
instrumentation-
amplifier circuits . The analog outputs are transformerless balanced and float-
ing (with 50
Ω
impedance) to ensure highest transparency and accurate pulse re-
sponse.