MQA: Aliasing, B-Splines, Centers of Gravity
The sampling theory formulated by Claude Shannon in the late 1940s had a key requirement: The signal to be sampled must be band-limitedthat is, it must have an absolute upper-frequency limit. With that single constraint, Shannon's work yields a remarkable result: If you sample at twice that ratetwo samples per period for the highest frequency the signal containsyou can reproduce that signal perfectly. Perfectly. That result set the foundation for digital audio, right up to the present. Cue the music.