Beat bins, asynchronies and muddy sounds: Shaping micro-time in grooves

In musical genres such as neo-soul and hip-hop, beats often have a temporal shape that makes their placement in time difficult to locate relative to a single point in time. This is often due to «muddy», processed sounds or asynchronies between events at beat-related metric positions. The beat bin theory suggests that the perceptual counterpart to such beat asynchronies or muddy beat shapes in a sounding groove is an internal (perceptual) reference structure of beat bins of considerable ‘width’ and a distinctive ‘shape’. I will start by pre- senting the theory and then focus on how various acoustic factors influence the beat bin, using examples from computer-based musical grooves. Ultimately, I argue that micro-level perception of, and synchronization to, sound is opti- mized for the task at hand, in line with the flexibility and dynamic nature of the human apparatus in perceiving, predicting, and processing rhythm.