Grass Valley AMX-3981 2014 - Manual (Page 94)

GUIDE TO INSTALLATION AND OPERATION
88 | AMX-3981
Final Stage
This final section of the processor is where the final look-
ahead peak limiter and bass soft clipper are adjusted. The
look-ahead limiters are wideband, limited to 6dB of gain
reduction, are extremely fast, and due to their look-ahead
nature are virtually transparent even at full gain reduction.
Their purpose is to control peaks that make it through the
multiband section. Adjustable parameters are:
• Final Limiter Drive: -6dB - +6dB (default: -5dB). Sets
the level at which the wideband sum of all bands is fed
to the final limiter.
• Output Level: -36dB - 0dB (default: -13dB for PGM1, -
11 dB for PGM2). Sets the output level for the current
preset. Can be used to match the measured loudness
of one preset to another. This is useful as more
aggressive presets will measure differently from less
aggressive versions.
6.5.4 Upmix using Linear Acoustic UpMAX tm
Surround Field Adjustments
The “surround field” can be adjusted with the Center channel Width
control and the Surround channel Depth control.
AutoMAX-II Transition Speed
When the upmix operates in AutoMAX-II
tm
mode, the speed of the
transitions from 2.0 to 5.1, and 5.1 to 2.0, can be configured to
provide smooth and unobtrusive changeovers.
• Set the “Upmix-to-Pass” and “Pass-to-Upmix” transition
speeds independently, over the range Instant to Very Slow
5.1/2.0 Detection Threshold
This parameter is used when the upmix operates in AutoMAX-II
tm
mode to detect silence on some of the 5.1 channels to determine if
5.1 or 2.0 is detected.
LFE Output Channel
The bass enhancement signal for the LFE channel is derived from
the Left, Center and Right channels. The LFE checkbox and LFE
Channel Level slider control the LFE output
Figure 6.19 ALC Module - Final Stage
Figure 6.20 ALC module - Upmix using UpMAX