3.5

Table Of Contents
579MainStage Instruments
Set the Ultrabeat filter type
The filter can operate in several modes, allowing specific frequency bands to be filtered
(cut away) or emphasized.
In MainStage, to select a filter type, click one of the following buttons:
LP (lowpass): This filter type allows frequencies that fall below the cutoff frequency
to pass. When set to LP, the filter operates as a lowpass filter. The slope of the filter
can be set to 12 or 24dB/octave in LPmode.
HP (highpass): This filter type allows frequencies above the cutoff frequency to
pass. When set to HP, the filter operates as a highpass filter. The slope of the filter
can be set to 12 or 24dB/octave in HPmode.
BP (bandpass): The frequency band directly surrounding the center frequency
(set with the Cutoff knob) is allowed to pass. All other frequencies are cut. The
Resonance parameter controls the width of the frequency band. The bandpass
filter is a two-pole filter with a slope of 6 or 12dB/octave on each side of the center
frequency of the band.
BR (band rejection): The frequency band directly surrounding the center frequency
(set with the Cutoff knob) is rejected, while the frequencies outside this band can
pass. The Resonance parameter controls the width of the rejected frequency band.
Set the Ultrabeat filter slope
Most filters don’t completely suppress the portion of the signal that falls outside the
frequency range defined by the Cutoff parameter. Frequencies that are located close to the
cutoff frequency are generally reduced less than those that are farther away. The higher
the slope value, the more apparent the level difference is between frequencies that are
near to the Cutoff frequency and those that are farther away from it.
In MainStage, click the 12dB or 24dB button. The slope (curve) chosen for the Filter
expresses the amount of rejection in decibels per octave. The steeper the slope, the
more severely the level of signals below the cutoff frequency is affected in each octave.