page 3 - 15
Aura8ip / Jan 2012
A u r a 8 i p P r o G U I
When the equalizer section is enabled the audio spectrum being influenced by the
equalization is represented by shaded areas of the audio spectrum. To show what we
mean, please refer to the next graphic.
Here we’ve created a bizarre (for example only!) curve to show how the shaded areas
represent the mathematical effects of the applied equalization. We’ve added low and high
frequency shelving to boost the signals at the extremes of the audio spectrum. We’ve
also used the two parametric equalizers in an overlapping fashion to create two scooped
out areas of the midrange. Note how the yellow curve (bottom) is very broad – this is
applying a very broad dip in the frequency response between about 100Hz and 3kHz.
However, notice that the green curve (top) is set to be rather narrow – much narrower
than the yellow curve on the bottom. The combined effect is a broad reduction in fre-
quencies between 100Hz and 350Hz and between 600Hz and 2.5kHz.
A Word About Our Limiters
Vorsis has returned the limiter to its rightful place as a device that only reacts to
control a peak in the audio level and only to the degree necessary to control that peak.
These limiters are not intended to be used to add their own signature to the audio; they
are there merely to prevent audio from exceeding a predetermined peak level.
In more conventional designs the limiters are sometimes found to be equipped with
gates, return to zero functions, temporary holds and even interband coupling. These
limiters typically need these functions to make up for deficiencies in the preceding
AGC or compressor – the limiters then act as a second, faster compressor to build den-
sity while, at the same time, are also tasked with controlling peaks. Conversely, Vorsis
designs utilize much better AGC and Compressor algorithms that allow the following
limiter to be just that, a limiter.
Unless the limiters have been tuned to create a very specific effect, there should nor-
mally be no more than 3dB of average gain reduction seen. At times, there may not be
any activity at all in a limiter band, however rest assured that the limiters ARE working
properly, they just don’t need gating and 12dB of gain reduction to do it!
Multiband Limiter
Before we begin discussing the multiband limiter it is important to recognize that the
number of limiter bands is controlled by the number of AGC/Com-
pressor bands as selected by the
Number of Bands
control discussed
in the AGC/Compressor section of this manual. Further, if the
number of bands control has been set to Broadband, we recommend
not enabling the remaining band of the multiband limiter – this
