Quasi-synchronous granular synthesis uses near-equal grain timing to produce amplitude modulation

In quasi-synchronous granular synthesis, grains are arranged in one or more streams where the delay between successive grains is equal or nearly equal. A single stream of grains spaced under 50 ms apart produces amplitude modulation: the ear hears a periodic volume oscillation at the inter-grain rate. Layering multiple streams with slightly offset delays blurs the quasi-periodic structure, so the sum approaches asynchronous synthesis. This positions quasi-synchronous synthesis between rigid AM and fully random granular clouds, enabling beating, tremolo, and textural-roughness effects unavailable at either extreme. Stream count and inter-grain jitter are the key control dimensions.

Examples

Three streams firing every 30, 31, and 32 ms each give a slight tremolo; together they produce a slowly beating, shimmering texture. Adding ±5 ms random jitter softens the beating into roughness.

Assessment

Explain why a single regular grain stream produces AM and how adding offset streams approaches asynchronous synthesis. Design a quasi-synchronous patch for a shimmering, beating texture and say which parameters you would map to modulation controllers.