TLDR:

"Oscillator sync forces one oscillator to reset in time with another - creating sharp, harmonically rich sounds and aggressive sweeps when you modulate the slave oscillator’s pitch."

What Is Oscillator Sync?

Oscillator sync is when one oscillator (the primary) forces another oscillator (the secondary) to restart its waveform cycle every time the primary completes its own cycle. This keeps the secondary oscillator locked in time with the primary, even if their pitches differ.

The result? Bright, ripping, harmonically rich tones - especially when you modulate the secondary’s pitch while the primary stays fixed.

Types of Sync

• Hard Sync: The secondary oscillator fully resets its waveform at each cycle of the primary. This creates sharp, harmonically complex tones.
• Soft Sync: The secondary tries to stay in phase with the primary without fully resetting - often producing more subtle, bendy sounds.

Use Cases

• Lead Sounds: Classic aggressive leads - like early analog synth solos - often use sync for their cutting tone.
• Harmonic Control: Sync keeps the waveform aligned, letting you control harmonic content while sweeping pitch.
• Sync Sweeps: Modulate the secondary's pitch while keeping the primary stable to create signature ripping effects.

Patch Tips

• Keep the primary oscillator at a fixed pitch.
• Send an envelope or LFO to modulate the secondary’s pitch - this creates dynamic tone movement.
• Experiment with waveform combinations - sync a saw with a sine, or a triangle with a folded wave.

Oscillator sync is a classic synthesis trick that still feels fresh. Whether you’re going for 80s leads or experimental textures, sync gives you harmonic control with tons of attitude.

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