A generally subjective assessment of how understandable something is. In music and acoustics this refers to how well we can discern specific information in a particular listening space. A space designed to have a high degree of intelligibility, such as a recording studio, will enable the listener to pick out subtleties in program material that will be masked in a less refined space, such as a gymnasium. Speech Intelligibility is a significant area of study in acoustics for obvious reasons. Here there are some well defined guidelines and objective criteria that can be used to design and rate not only the space itself, but a sound reinforcement system placed within it.