page 3 - 8
Aura8ip / Jan 2012
A u r a 8 i p P r o G U I
The Aura8ip’s eight processing sections are completely independent, so each pro-
cessor may be operated in any band count desired.
Aura8ip has very flexible phase-linear crossovers which operate at
24dB/ocatave (4th order). Each crossover may be adjusted within a
wide frequency range:
- The BAND 1-2 crossover is adjustable between 20Hz and 687Hz in 3 band mode,
or 20Hz and 20kHz in 2 band mode. This band has a wide adjustment range in order
to accommodate the requirements of running in two band mode
- The BAND 2-3 crossover has a range of 728 to 20 kHz.
Making the crossover settings by ear is the best way to discover how to set the cross-
overs for the best sound on the type of material being processed.
In “3 Band” mode, the BAND 1-2 crossover will usually end up between 80 and 300
Hz while the BAND 2-3 crossover will fall somewhere between 800Hz and 3kHz.
In “2 Band” mode the Band 1-2 crossover will be found somewhere in the range
between 120Hz and 400Hz. There is no Band 2-3 crossover setting when the processing
is in two band mode because in that mode there is no Band 3.
In Broadband mode there are no crossover settings because there is no crossover to
adjust.
Crossovers
The purpose of a crossover (Xover) is to separate the audio spectrum into different
frequency bands prior to processing. The reason this is done is to eliminate or reduce the
effects of gain control happening in one part of the spectrum from affecting another. For
example, processing bass-heavy material with a broadband (1 band) processor almost
inevitably results in an effect called “spectral gain intermodulation,” which simply means
that the gain is being arbitrarily changed in one part of the audio spectrum because of
signals in another part of the spectrum that need the gain to be changed. Unless this
is done to create an effect, spectral gain intermodulation can be annoying as well as
fatiguing to listen to.
Comparison of AGC controls visible in 3 band mode (left),
2 band mode (center), and broadband mode (right)