Capping wavetable harmonics at the limit of hearing rather than Nyquist saves memory

A wavetable does not have to carry every harmonic that fits under Nyquist — most listeners cannot hear near 20 kHz (adults are lucky to reach 14 kHz), so the topmost harmonics are inaudible anyway. Deliberately capping the harmonic count at the practical limit of hearing (a ‘middle ground’) reduces table size and the aliasing budget while sacrificing nothing audible. Fewer harmonics also means shorter tables and less memory per subtable. The trade-off is explicit: choose more harmonics for provably transparent quality, or fewer to save memory and CPU, judged against real human hearing rather than the theoretical Nyquist ceiling.

Examples

Instead of 551 harmonics for a 40 Hz table (top harmonic ~22 kHz), choosing 368 puts the top harmonic at 14.72 kHz — above what most adults hear — so the reduction is inaudible yet meaningfully cheaper. Its alias folds back to about 14.66 kHz, also effectively inaudible.

Assessment

Explain why an anti-aliased wavetable might intentionally include fewer harmonics than Nyquist allows, and describe the quality-versus-memory trade-off this decision represents.