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Aura8ip / Jan 2012
A u r a 8 i p P r o G U I
Those who may be concerned about “… adding gain after AGC/
Compression because it will increase noise…” need to know that
the signal processing chain inside Aura8ip has 144dB of dynamic
range. This is approximately 50dB more dynamic range than a
digital CD. Therefore “noise” is of no concern whatsoever – the
processing chain will remain absolutely dead quiet regardless of
the amount of Makeup Gain that may be required.
Note also that the amount of Makeup Gain is somewhat de-
pendent on the Compression Ratios being applied to the signals in each processing
band. The higher the Compression Ratio, the tighter the output level is regulated, and
therefore the more Makeup Gain that will be required. However, the difference in the
Makeup Gain required with 20dB of compression at a 4:1 ratio and that required at
20dB compression with a 10:1 ratio is only around 3dB.
Parametric EQ
The Aura8ip is equipped with a flexible equalizer section which may be used to
sweeten the spectral balance. The equalizer provides a graphical representation of the
equalizer’s contribution to the audio by creating shaded areas in the graph represent-
ing the mathematical result of an overlapping equalizer sections.
The equalizer may be placed before or after the
AGC/Compressor stage, and though the audible ef-
fects of each placement are different (and sometimes
subtle) they are important to understand. We will
discuss this shortly.
The equalizer has two parametric sections (adjustable frequency, boost/cut, and
Q) and two shelving filters (adjustable frequency and boost/cut). The shelving filters
behave somewhat like tone controls on consumer audio equipment, and provide a
broad, low-Q boost or cut at the extremes of the audio spectrum.
The two parametric sections provide a broad or narrow boost or cut to any fre-
quency within the 20Hz to 20kHz audio spectrum, and may even overlap to create
special EQ curves.
