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Table Of Contents
216 Chapter 20 ES2
Filter Slope
A filter can not completely suppress the signal portion outside the frequency range
defined by the Cutoff Frequency parameter. The slope of the filter curve expresses the
amount of rejection applied by the filter (beneath the cutoff frequency) in dB per octave.
Filter 2 offers three different slopes: 12 dB, 18 dB and 24 dB per octave. Put another
way, the steeper the curve, the more severely the level of signals below the cutoff
frequency are affected in each octave.
Fat
Increasing the Resonance value results in a rejection of bass (low frequency energy)
when using lowpass filters. The Fat button (located below the filter slope buttons)
compensates for this side-effect, delivering a richer sound.
Filter Mode (Lo, Hi, Peak, BR, BP)
Filter 1 can operate in several modes, allowing the filtering (cutting away) and/or
emphasis of specific frequency bands.
 A lowpass filter allows frequencies that fall below the cutoff frequency to pass. When
set to Lo, the filter operates as a lowpass filter. The slope of Filter 1 is 12 dB/octave in
Lo mode.
 A highpass filter allows frequencies above the cutoff frequency to pass. When set to
Hi, the filter operates as a highpass filter. The slope of Filter 1 is 12 dB/octave in Hi
mode.
 In Peak mode, Filter 1 works as a Peak Type Filter. This allows for a level increase in a
frequency band, the width of which is controlled by the Resonance parameter.
 The abbreviation BR stands for band rejection. In this mode, the frequency band (a
range of adjacent frequencies) directly surrounding the cutoff frequency is rejected,
whilst the frequencies outside this band can pass. The Resonance parameter controls
the width of the rejected frequency band.