EVOC 20 TrackOscillator oscillator controls in Logic Pro

The tracking oscillator follows the pitch of incoming monophonic audio signals and mirrors these pitches with a synthesized sound. The FM tone generator for the tracking oscillator consists of two oscillators, each of which generates a sine wave. The frequency of Oscillator 1, the carrier, is modulated by Oscillator 2, the modulator, which deforms the sine wave of Oscillator 1. This results in a waveform with rich harmonic content.

Important: The parameters discussed in this section are available only if the Synthesis In menu is set to Osc. See Synthesis In controls.

Figure. Basic Tracking Oscillator parameters.

Tracking oscillator parameters

  • FM Ratio field: Set the ratio between Oscillators 1 and 2, which defines the basic character of the sound. Even-numbered values or their multiples produce harmonic sounds, whereas odd-numbered values or their multiples produce inharmonic, metallic sounds.

    • An FM Ratio of 1.000 produces results resembling a sawtooth waveform.

    • An FM Ratio of 2.000 produces results resembling a square wave with a pulse width of 50%.

    • An FM Ratio of 3.000 produces results resembling a square wave with a pulse width of 33%.

  • FM Int knob: Determine the intensity of modulation. Higher values result in a more complex waveform with more overtones.

    • At a value of 0, the FM tone generator is disabled and a sawtooth wave is generated.

    • At values above 0, the FM tone generator is activated. Higher values result in a more complex and brighter sound.

  • Coarse Tune field: Set the pitch offset of the oscillator in semitones.

  • Fine Tune field: Adjust the tuning in hertz.

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