Apple MainStage 3 Instruments - MainStage 3 Instruments

Resonance
The resonance control emphasizes or suppresses signals around the cutoff frequency.
The figure below shows an ES1 sawtooth wave with a high resonance setting and the cutoff
frequency set to 660 Hz.
This resonant filter setting results in much brighter and harsher signals close to the cutoff
frequency. Frequencies below the cutoff point are not affected.
The result of using filter resonance is a change in the basic waveform shape and, therefore, the
timbre of the sound.
Very high filter resonance settings can cause the filter to self-oscillate, resulting in the filter
generating an audible sine wave.
Filter drive
Filter drive adds an amount of gain to the waveform as it enters the filter—an input gain
control—overdriving the filter and distorting the waveform. This waveform distortion changes
the timbre of the sound, making it much harsher.
The figure shows an unfiltered sawtooth wave, with drive set to a value of 80%. Note the wave
cycles touching the floor and ceiling of the filter’s dynamic range.
Appendix B Synthesizer Basics 485