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AirAura X1 / Dec 2016
A i r A u r a X 1 P R O G U I
FM & HD Analysis Options Type
•
FFT – Displays the spectral output of the FM or
HD processing paths after processing. The FM
display includes any pre-emphasis being used in
order to present an accurate view of the signal
actually being sent to the transmitter by the X1.
•
3-D Plot
– A three-dimensional plot of the audio,
after processing, which displays signal amplitude
versus frequency versus time. The display has a
ten second historical window depth allowing some
historical perspective about the FM or HD audio
after processing.
•
Loudness – Displays a meter which shows the
long and short term loudness of the audio processing
•
O-Scope – Displays the audio waveforms at the output of the FM or HD processing
chains.
•
E vs F – Displays the measured RMS Loudness.
•
SDR™ – Spectral Dynamic Range™. This display shows the amount of dynamic
range within 31 ISO frequency bands after processing.
•
Stereo
– Displays a meter which shows the L+R/L-R ratio from 0 to 1.0.
•
A-Clip
– This is AirAura’s final FM clipper activity display that shows where in
the audio spectrum distortion products are being detected and reduced and by how
much.
A detailed explanation of each analysis type follows.
FFT
This display shows a Fast Fourier Transform of the audio spectrum after processing
has been applied by the final FM clipper or HD limiter. The FFT display’s high resolution
is useful for locating where in the audio spectrum certain signals are heard. With complex
program material the FFT gives good visual feedback on the levels of audio residing in
different parts of the audio spectrum.
