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Table Of Contents
214 Chapter 20 ES2
To check out how the overdrive circuit between the filters works, program a sound as
follows:
 Simple static waveform (a sawtooth)
 Filter set to Series mode
 Filter Blend set to 0 (center position)
 Filter 1 set to Peak Filter mode
 High Resonance value for Filter 1
 Modulate Cutoff Frequency 1 manually or in the Router.
 Set Drive to your taste.
 Filter away (cut) the high frequencies with Filter 2 to taste.
The sonic result resembles the effect of synchronized oscillators. At high resonance
values, the sound tends to scream. Modulate the Resonance of Filter 1, if you wish.
Filter Parameters
This section covers the ES2 filter parameters in detail.
Cutoff and Resonance
With every lowpass filter (in the ES2: Lo mode for Filter 1 and all of Filter 2’s modes), all
frequency portions above the Cutoff Frequency (Cut) are suppressed, or cut off, hence
the name. The Cutoff Frequency controls the brilliance of the signal. The higher the
Cutoff Frequency is set, the higher the frequencies of signals that are allowed to pass
through the lowpass filter.
Note: The dynamic lowpass filter is the most essential module in any subtractive
synthesizer. This is why Filter 2 always operates in lowpass mode.
Resonance (Res) emphasizes the portions of the signal which surround the frequency
defined by the Cutoff Frequency value. This emphasis can be set so intensively in Filter
2, that the filter begins to oscillate by itself. When driven to self-oscillation, the filter
outputs a sine oscillation (sine wave). This self-oscillation can be supported by the Filter
Reset parameter. See “Flt Reset on page 215 for details.