Real-time waveform substituting sound engine

A sound engine in a processor-based system utilizing real-time synthesis optimizes synthesis time, maximizes the number of fully-synthesized sound requests and preserves currently excessive sound requests. During synthesis, the sound engine attempts to full-synthesize all requests. If the sound engine determines that remaining sound requests are excessive and cannot be fully-synthesized, it preserves each excessive request by synthesizing a substitute waveform segment. If the sound engine determines that limiting the number of preserved requests is required, it synthesizes a concluding waveform segment for and then discards selected requests during selected synthesis intervals. Both substitute-synthesis and discarding of sound requests are achieved with minimized detrimental impact on ongoing sound performances.