This Recommendation specifies an advanced sound system with and without accompanying picture, beyondsystems specified in Recommendation ITU-R BS.775. An advanced sound system uses audio data incombination with an appropriate set of metadata to specify a sound scene to be delivered/broadcasted. Thespecifications include requirements for signalling the properties of advanced sound content and speakerlayout to be used in content production for advanced sound systems. The advanced sound system can applyto the sound component of television and expanded large screen digital imagery (LSDI) programmes, as wellas for sound only programmes.