Retro Synth Sync oscillator in Logic Pro for iPad
The synthesizer oscillators are used to generate one or more waveforms. You set the basic tonal color with the chosen waveform or waveforms, adjust the pitch of the basic sound, and set the level relationships between oscillators. The signal of one or both oscillators is then sent to other parts of the synthesizer engine for shaping, processing, or manipulation. See filter controls, amp and effect controls, modulation, and global and controller settings.
Oscillator sync sounds are typically more aggressive than sounds generated with other synthesis methods, making this engine most suitable for lead and hard bass instruments. On each waveform cycle of oscillator 1 the waveform of oscillator 2 is reset to its start position, thus oscillator 2 is hard synced to oscillator 1.

Sync oscillator 1 and 2 parameters
Oscillator 1/2 Waveform buttons: Choose the type of waveform that each oscillator generates. The waveform is responsible for the basic tonal color. The oscillators output a number of standard waveforms—sawtooth, square, and triangle.
Osc 1/2 PW knobs and fields: Adjust the pulse width (shape) of the square waveform when chosen for oscillator 1 or 2. This makes the square waveform more rectangular and nasal-sounding.
Oscillator 2 Sync slider and field: Set the maximum amount of sync modulation. This makes the sound more or less aggressive. Technically, this control raises the pitch of oscillator 2 in relation to oscillator 1.
Sync oscillator modulation and mix parameters
Shape Mod knob and field: Set the oscillator sync modulation intensity. The centered (off) position disables all waveform (oscillator sync) modulation with the LFO or filter envelope.
Left of center = LFO modulation.
Right of center = Filter Envelope modulation.
Vibrato Depth knob and field: Rotate to set the amount of vibrato (pitch modulation).
Oscillator Mix slider and field: Move to crossfade (set the level relationships) between the oscillators.
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