Omnia 6 Use and Installation Guide – Version 1.00a
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Input Source
Selects between the discrete Left/Right Analog input or the AES/EBU Digital input.
Input Mode
Selects how input audio is routed and processed by the Omnia-6fm. Highlight and click on the parameter
selection to set the mode. The selected Mode is shown with a dot in the box next to the name. The factory
default selection is Stereo. The other available modes are:
Stereo: the left and right input channels are processed separately.
Mono L: routes the Left Input only through both channels of the processor.
Mono R: routes the Right Input only through both channels of the processor.
Mono L + R: sums the stereo input to mono and processes the summed audio.
Swap L / R: swaps the Left and Right Inputs.
Invert Both: if the absolute phase of the Omnia-6fm is different from your existing system, it could
cause your announcers to think they sound “weird” when speaking while monitoring
through headphones. If this happens, the absolute phase of the Omnia-6 may be different
from what your announcers are used to. A quick way to remedy this is to highlight Invert
Both and click to select. A dot in the box indicates Invert Both is active.
High-Pass Filter
In most FM systems, subsonic frequencies should usually be rolled off to prevent difficulties with certain
exciters and STL systems. The Omnia6-fm has a third-order (18dB/Octave) high pass filter with five
selectable cutoff frequencies from 60 Hz down to 20 Hz. The factory default is "Out", which means that
frequencies down to around 2Hz are passed through the system without attenuation. You may select one of
the other values that may be more appropriate for your system.
Phase Rotator
This section consists of three cascaded second order 200 Hz allpass filter sections. Phase Rotators (also
known as Phase Scramblers) are commonly utilized to make asymmetrical waveforms (such as voice) more
symmetrical. This ensures that clipping occurs equally on positive and negative peaks, making better use of
the symmetrical nature of FM modulation. Phase rotation can make talent voice sound cleaner, but since it
disturbs the phase integrity of musical signals, music might sound more faithful to the original source if
phase rotation is reduced or not used at all. The four available settings (Off, 1, 2, 3) allow you to select how
many sections (if any) are active. Selecting higher numbers will result in a steeper phase shift slope at the
design frequency of 200Hz. You should always choose the Phase Rotator setting that sounds best in your
system. Off can be chosen if previous phase rotation has been performed in your system (in a mic processor
for example) or to preserve the phase integrity of the original program as described above.
