Output Configuration - Omnia .9 Installation & User Manual

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Output Configuration

Connect the audio outputs as appropriate for your installation. Omnia.9 supports balanced professional line-level analog
audio outputs via its Left and Right Outputs in the Main Analog I/O section of the rear panel, two AES/EBU digital outputs on
standard XLR connectors in the Main Digital I/O section, an additional AES/EBU digital output in the Aux Digital I/O section,
two composite MPX outputs in the Composite I/O section and Livewire+ AES67.Omnia Direct (MPX over AES/EBU is also
supported from Main FM Out 1 and/or 2.
Return to the I/O Options menu, then select Main Outputs. Drop-down menus are provided to assign the outputs and set the
levels of the Analog Out XLR jacks and the three AES/EBU XLR outputs (Main FM Out 1, Main FM Out 2, Aux Out).. Default
output audio choices include FM Pre-final L/R, AM, HD-1, HD-2, HD-3, Headphone Out, Speaker Out and more.
A complete explanation of these controls can be found in the System Menu section of the full user manual.
Pre-emphasis options and the stereo generator (MPX) output level / stereo pilot level controls can be found in I/O Options /
FM Options.
FM Diversity Delay, if needed, can be set from I/O Options / Diversity Delay.
Omnia.9 is set up by default to provide a pre-emphasized composite MPX signal from the Omnia.9's built-in stereo generator.
If you must use an external stereo generator, some additional configuration is required:
Note:
Feeding the transmitter with L/R pre-emphasized output instead of the MPX output has several inherent
performance disadvantages, including the loss of peaks beyond 91% (leaving room for the 19kHz pilot
tone, as we will not know its phase) - a capability unique to the MPX clipper. RDS and Auto Pilot also become
unavailable, though the L/R clipper does employ psychoacoustic distortion masking.
From the Home menu, go to System, then System Configuration, then Processing Paths. The default setting for the "FM:"
dropdown is "MPX Only". In order to add the output choices needed for FM L/R audio, choose either "L/R Only" if you
are you do not intend to use Omnia.9's built-in stereo generator at all or "MPX + L/R" if you plan to use the built-in stereo
generator for your main output, but need an additional pre-emphasized L/R output to feed a secondary chain. Select "Apply
Configuration" to put the changes into effect. A confirmation dialog will appear. Clicking "Yes" will cause the Omnia.9 to
reinitialize, which will take your station off the air for a few seconds.
Finally, from the Home menu, go back to System, then I/O Options, then Main Outputs to select the Output Mode. Now "FM
Pre-emph L/R" and "FM De-emph L/R" will be among the available choices. Output levels are also adjusted here and The AES
Main FM Out 1 and/or 2 outputs can be set to output Omnia Direct ™ (MPX over AES/EBU) if desired instead of the default
"L/R Audio".
Note:
FM De-emphasized L/R is the least-recommended output option, especially for analog. Although is it the-
oretically possible to have excellent peak modulation control even with external pre-emphasis, in practice
stereo generators vary widely in implementing pre-emphasis. Certain stereo generators use phase-linear
pre-emphasis in DSP, which is incorrect and causes roughly 20% overshoot (2dB loudness loss) when
used with any audio processor. We recommend connecting the output of your stereo generator to one of
Omnia.9's composite inputs, watching the Left De-mod waveform on the oscilloscope, and comparing it to
L/R Output - Left Pre-emph. If you see high frequency peak overshoots, the stereo generator may be poorly
designed, and must either be replaced or have its pre-emphasis disabled, with Omnia.9's output set to FM
Pre-emphasized.
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