•
Note:
FM De-emphasized L/R is the least-recommended output option, especially for analog.
Although is it possible in theory to have excellent peak modulation control even with external pre-
emphasis, in practice not every stereo generator does pre-emphasis correctly. 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.
If you using the composite outputs, navigate to the
System > I/O Options > FM Options
menu to set the
pre-emphasis, pilot injection, audio bandwidth, and single/dual sideband preference. Select the proper
output source for each composite output and adjust the output level to achieve the desired modulation
level.
Omnia.7 is set up by default to provide a pre-emphasized MPX signal from the FM processing core. 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. The (optional) internal RDS encoder also becomes unavailable, though the L/R clipper does
employ psychoacoustic distortion masking.
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