8. Software Installation
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VSXNET Subwoofer Operation Manual rev 2.0.0
Audio Processing
VNET provides the following processing options:
Crossover filtering with frequency variable over the range 10 Hz to 25 kHz (and Out ) with the
following alignments:
• 1st order
• 12 dB/Octave Bessel
• 12 dB/Octave Butterworth
• 12 dB/Octave Linkwitz-Riley
• 18 dB/Octave Bessel
• 18 dB/Octave Butterworth
• 24 dB/Octave Bessel
• 24 dB/Octave Butterworth
• 24 dB/Octave Linkwitz-Riley
The Low band has a low-pass crossover filter, and the High band has a high-pass and a low-pass
crossover filter.
• A 2nd order low-shelf filter with frequency variable over the range 10 Hz to 25 kHz, and boost/cut
from -15 to +15 dB.
• A 2nd order high-shelf filter with frequency variable over the range 10 Hz to 25 kHz, and boost/cut
from -15 to +15 dB.
• Eight bands of bell (parametric) equaliser, each band having frequency variable over the range
10 Hz to 25 kHz, bandwidth variable from 0.1 to 5 octaves, and boost/cut from —15 to +15 dB.
• Delay adjustable up to 200 ms.
• Adjustable gain from —30 to +15 dB, and mute.
Equalisation Filters
The eight Bell filters (Parametric equalisation filters) may each be used to emphasise (by applying a positive Level parameter
setting) or de-emphasising (by applying a negative Level parameter setting) a range of frequencies centred on the setting of the
Frequency parameter, and encompassing a frequency range determined by the Bandwidth parameter setting.
The two shelving filters allow all frequencies below that of the frequency parameter (for the Low shelf) or all frequencies above
that of the frequency parameter (for the high shelf) to be emphasised (by applying a positive Level parameter setting) or de-
emphasised (by applying a negative Level parameter setting).
Crossover Shapes
In addition to the usual Butterworth, Linkwitz-Riley and Bessel filter shapes, VNET processing provides access to Hardman
crossover filtering. Hardman filters produce much steeper cut-off slopes for a given order than conventional crossover
alignments, without any additional group delay. This allows a lower order filter to be used without sacrificing cut-off
characteristics, but with smoother group delay and less severe phase penalties, giving a more natural sound. Hardman filters
and also provide identical phase characteristics between adjacent bands (like Linkwitz-Riley), so the polar performance is
rock steady.
We also employ phase matching on our Bessel filters, so adjacent bands are in-phase throughout the crossover region.