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AirAura X1 / Dec 2016
A i r A u r a X 1 P R O G U I
When the BS.412
is switched on
, the MPX Power controller is then engaged and the
algorithm immediately applies the measured MPX Power correction to the processed
output.
After the MPX Power Controller is first engaged allow a full minute for the
MPX Power to settle to its final value.
As the controller measures and integrates the MPX energy over time the drive to the
processing will be modified until the measured MPX power satisfies the reference level as
set by the Stereo Encoder menu’s BS.412 control. The control’s “0dB” setting conforms
to the current ITU-R BS.412-7 Multiplex Power standard.
There are some options in fine tuning the MPX power controller that are available
in X1. These additional controls will never allow MPX power to EXCEED the legal
maximum, instead they allow a tradeoff between subjectively “clean” or “aggressive”
setting of the MPX power controller.
BS.412 Peak Style (BS.412 MPX Power Control)
The BS.412 peak style control allows two options. Normal allows for very
strict control of modulation of the signal in conjunction with MPX power
management. In the “Peaky” mode, short duration peaks which do not affect
total MPX power are allowed which can create a less restrictive sound. This
is done dynamically by modifying the threshold of the distortion controller
in the X1’s left/right clipper and filter stage.
To change this setting, left click on the knob and use the mouse wheel
to switch between NORMAL and PEAKY. Left click again to confirm your
choice.
BS.412 Speed (BS.412 MPX Power Control)
Adjusts the secondary recovery speed of the MPX Power control loop while
the primary recovery speed remains program controlled. Higher settings result
in faster release times of the secondary release.
To change the control, left click on the knob and use the mouse wheel to
increase or decrease the value.
BS.412 MPX Power (BS.412 MPX Power Control)
This control sets the maximum permitted multiplex power according to the
BS.412 measurement algorithm. The control has a range from -3dB to +6dB in
0.1dB steps. This resolution allows small adjustments in actual MPX Power to
allow for the maximum amount of power allowed by the local regulatory body.
To change the control, left click on the knob and use the mouse wheel to
increase or decrease the value.
BS.412 Calibration Offset (BS.412 MPX Power Control)
Adjusts the threshold of the power detector to modify its calibration. The
control range is -18dB to 0dB. To change the control, left click on the knob
and use the mouse wheel to increase or decrease the value.