23
EQUALISER
The equaliser section consists of an analogue modelled 5 band parametric
equaliser with a wide range of frequency and bandwidth. Up to 18dB boost
or Cut is available on each band. Bass and Treble bands have selectable
Shelf or Bell(Peaking) filter shapes whereas the 3 mid bands are bell only.
All bell filters have a frequency range from 32Hz to 22kHz in 1 semitone
steps. Bandwidth range is from 0.08 octave (1 semitone) to 5 Octaves.
The graphical display shows a plot of the selected frequency curve. When
each band is selected, a small vertical bar appears across the 0dB line on
the graph. This indicates the centre frequency of the selected band, which is
useful in locating the position of each band, either before Cut or Boost is
applied, or when a complex EQ curve is in use.
EQ GAIN MANAGEMENT
Since both the Dynamic EQ, Compressor and Parametric Equalisers are
capable of increasing overall gain, the GAIN MANAGEMENT treats them
as a single set of functions, since gain applied in the dynamic EQ or
Compressor can be reduced again in the main EQ. Once both EQ
=
s have
been adjusted for best results, use Gain Trim on either DQ or EQ pages to
reduce gain to keep Gain Reduction to a minimum.
If the gain is not trimmed to keep gain reduction to a minimum, the signal
will, in effect be limited, which can alter the subjective nature of the sound
being processed.
THREE BAND PROCESSING
The main purpose of the split band section is to allow the three different
parts of the audio spectrum to be treated independently so as to minimise
side effects, but each of the dynamic processes may be adjusted differently
in each of the three bands if required. This opens up many creative
possibilities for introducing level dependent spectral changes.
The user may adjust the two crossover points that define the three frequency
bands into which the signal is split prior to processing. The crossover
frequencies may be accessed from the second page of any of the split-band
effects blocks.
3 BAND EXPANDER/GATE
Expanders are generally used to remove unwanted noise during what should
be passages of silence, but are also a means of
>
undoing
=
gain at very low
levels due to compression, where the noise floor is pulled up to an
unacceptably high level. Threshold, Ratio, Attack, Release and Range
adjustments allow a wide range of control, with Program Adaptive techniques
used to make real time adjustments depending on the nature of the signal.
The incoming signal levels of each band are displayed in the Threshold box,
rising from
!
96dB towards 0dB. Rotating the knob clockwise takes the wider
threshold bars down towards the signal. As the signal approaches threshold,
the gate begins to open at the Attack rate until, as the two bars touch, the
gate will fully open. This gives a clear indication at all times of where the
signal is in relation to the threshold. As the signal level drops below the
threshold bar, the expander begins to reduce gain by an amount dependent
on the Ratio setting and at the Release rate. The onset of expansion causes
the appropriate expander LED under the main output VU meters to illuminate.
The Range control is used to limit the maximum amount of expansion,
regardless of Ratio settings. This can be used to prevent excessive expander
activity and improve transparency.
3 BAND BOOTSTRAP COMPRESSOR
The purpose of the Bootstrap Compressor is to pull signals up towards digital
full scale. This combined with Program Adaptive algorithms provides punch,
enhances spectral detail and delivers well controlled power. Threshold, Ratio,
Attack, Release and Gain adjustments are available. Simply increase
Threshold and Ratio.
