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loud, clean low end, with no sacrifice to the overall loudness of your signal. The Deep Bass and Phat Bass
parameters are found under the Bass menu. Deep Bass is a shelf boost at 90 Hz that utilizes a phase linear 12
dB/octave slope to produce the shelving EQ function. Phat Bass is a unique enhancement that adds filtered
harmonics to the bass frequencies. Low frequency texture is emphasized with this parameter. Older materials
sound fuller (or phatter) with the added illusion of loudness.
Warmth EQ:
The Warm Bass parameter is found under the Warmth menu. Warm Bass is a shelf boost that
functions up to 150 Hz. Adjusting Warm Bass compensates for program material that is naturally lacking in
upper-bass punch. The parameter is adjustable over a 6 dB range.
Phase Linear, Time Aligned Crossover:
Most multiband audio processors must make a compromise in the
crossover area: either provide true phase linearity, or dynamic flat response. The problem with implementing
only the former is that, under dynamically controlled conditions, peaks or notches will occur at the crossover
frequencies once the bands are recombined. In an effort to minimize this problem in older designs, crossover
frequencies were phase-offset, so when they were recombined, these peaks and notches would be minimal—
thus maintaining some degree of flatness. Such a compromise results in the loss of phase linearity, which
reduces clarity. In Omnia-3’s DSP implementation, the crossover network is carefully time-aligned so the
recombined spectrum remains flat, regardless of the amount of gain control being applied within any band. This
yields a phase linear response, so that no harmonic content is ever displaced in time. The result: a truer, more
natural sound without smearing.
Multiband AGC Section (Omnia-3fm Turbo Only):
Similar in character to the wideband AGC described
above, but expanded to three bands, this section has the ability to add significant power, consistency and
loudness to the audio while tailoring and pre-processing it for delivery to the multiband limiter section.
Multiband Dynamic Peak Limiter:
These are not just simple limiter sections using single time constants, but
rather a process that can make adjustments based upon the “peak weight” of the signal. The sophisticated
algorithm relies upon a
peak-weighted
calculation to determine the strength of a transient peak. It then
determines if very fast dynamic control is required. In this fashion, faster timing is used only when necessary,
and then only under certain conditions that are dictated by the density of the peak signal. If the peak is very
short in nature, then the limiter will ignore it and let it pass onto the next processing stage (the final
limiter/clipper). A built-in
Hold
feature allows the limiter to rest momentarily in order to reduce IM distortion.
Non-Aliasing, Distortion Controlled Final Limiter:
This is where other DSP attempts have failed, resulting in
“digital grunge” and the unflattering phrase “that digital sound.” Omnia-3’s proprietary method generates no
aliasing products and does
not
need to over-sample the audio data, thus conserving valuable DSP power. This
reduces audible processing distortion while producing a clean, loud signal. Users have reported that this
implementation exceeds the “smoothness” of a well-designed analog limiter.
Stereo Generator /Encoder (Omnia-3fm Turbo only):
With an all-digital, numeric implementation,
theoretically perfect performance is approached. Stereo separation is typically greater than 65 dB. Suppression
of the 38 kHz carrier is greater than 75 dB. User parameters include separation, pilot phase, pilot level and
composite output level.
Selectable Composite Clipper with Phase Linear Composite Low Pass Filter (Omnia-3fm Turbo only):
This
feature is provided for those who wish to add an “afterburner” to their FM signal. This clipper does not interfere
with the 19 kHz pilot, because the pilot is added post-clipper. There is also a digital implementation of the
Dividend
Composite Filter, which allows composite processing to be used without generating
any
harmonic
content in the SCA spectrum. With 3 dB of composite processing employed, all content above 53 kHz is
suppressed by 75 dB. This precise spectral management contributes to loudness, since it ensures that no wasted
energy is transmitted.
