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Table Of Contents
Using the ES1 Filter Parameters
This section outlines the filter parameters of the ES1.
Cutoff slider: Controls the cutoff frequency of the ES1’s lowpass filter.
Resonance slider: Cuts or boosts the portions of the signal that surround the frequency
defined by the Cutoff parameter. Boost can be set so intensively that the filter begins
to oscillate by itself (see Driving the ES1 Filter to Self-Oscillation).
Tip: You can simultaneously adjust the cutoff frequency and resonance parameters by
dragging vertically (cutoff) or horizontally (resonance) on the word Filter, found between
the Slope buttons.
Slope buttons: The lowpass filter offers four different slopes of band rejection above
the cutoff frequency. The four settings are arranged clockwise from the top left, as
follows:
24 dB classic: Mimics the behavior of a Moog filter. Turning up the resonance results
in a reduction of the low end of the signal.
24 dB fat: Compensates for the reduction of low frequency content caused by high
Resonance values. This resembles the behavior of an Oberheim filter.
12 dB: Provides a soft, smooth sound which is reminiscent of the early Oberheim
SEM.
18 dB: Tends to resemble the filter sound of Roland’s TB-303.
Drive slider: An input level control, which allows you to overdrive the filter. Use it to
change the behavior of the Resonance parameter, which will eventually distort the
sound of the waveform.
Key slider: Controls how strongly the keyboard pitch (the note number) modulates the
filter’s cutoff frequency:
If Key is set to zero, the cutoff frequency won’t change, no matter which key you
strike. This makes the lower notes sound relatively brighter than the higher ones.
37Chapter 4 ES1