Despite: the increasing interest in multimedia data retrieval audio data has received little attention. This is due, not to a lack of interest but rather to unique difficulties posed by the medium. In particular existing unstructured audio representations do not easily lend themselves to content based retrieval and especially browsing. This paper aims to address hs oversight by developing an audio representation that provides direct support for browsing and content based retrieval. This support is the result of a structured representation based on psychoacoustic ptincip1.e~in which salient attributes of audio are directly accessible. In addition, the representation is compact thus addressing the requirement for minimisation of storage.