An apparatus, comprising: an interface system; and a logic system configured for: receiving, via the interface system, audio reproduction data comprising one or more audio objects and associated metadata; wherein the audio reproduction data has been created with respect to a virtual reproduction environment comprising a plurality of speaker zones at different elevations; receiving, via the interface system, reproduction environment data comprising an indication of a number of reproduction speakers of an actual three-dimensional reproduction environment and an indication of the location of each reproduction speaker within the actual reproduction environment; mapping the audio reproduction data created with reference to the plurality of speaker zones of the virtual reproduction environment to the reproduction speakers of the actual reproduction environment; and rendering the one or more audio objects into one or more speaker feed signals based, at least in part, on the associated metadata, wherein each speaker feed signal corresponds to at least one of the reproduction speakers within the actual reproduction environment, characterized in that: the metadata associated with each audio object includes an audio object position, and speaker zone constraint metadata indicating whether rendering the respective audio object involves imposing speaker zone constraints, and wherein rendering the respective audio object depends on the audio object position, and includes imposing speaker zone constraints in response to the speaker zone constraint metadata. an interface system; and a logic system configured for: receiving, via the interface system, audio reproduction data comprising one or more audio objects and associated metadata; wherein the audio reproduction data has been created with respect to a virtual reproduction environment comprising a plurality of speaker zones at different elevations; receiving, via the interface system, reproduction environment data comprising an indication of a number of reproduction speakers of an actual three-dimensional reproduction environment and an indication of the location of each reproduction speaker within the actual reproduction environment; mapping the audio reproduction data created with reference to the plurality of speaker zones of the virtual reproduction environment to the reproduction speakers of the actual reproduction environment; and rendering the one or more audio objects into one or more speaker feed signals based, at least in part, on the associated metadata, wherein each speaker feed signal corresponds to at least one of the reproduction speakers within the actual reproduction environment, characterized in that: the metadata associated with each audio object includes an audio object position, and speaker zone constraint metadata indicating whether rendering the respective audio object involves imposing speaker zone constraints, and wherein rendering the respective audio object depends on the audio object position, and includes imposing speaker zone constraints in response to the speaker zone constraint metadata. receiving, via the interface system, audio reproduction data comprising one or more audio objects and associated metadata; wherein the audio reproduction data has been created with respect to a virtual reproduction environment comprising a plurality of speaker zones at different elevations; receiving, via the interface system, reproduction environment data comprising an indication of a number of reproduction speakers of an actual three-dimensional reproduction environment and an indication of the location of each reproduction speaker within the actual reproduction environment; mapping the audio reproduction data created with reference to the plurality of speaker zones of the virtual reproduction environment to the reproduction speakers of the actual reproduction environment; and rendering the one or more audio objects into one or more speaker feed signals based, at least in part, on the associated metadata, wherein each speaker feed signal corresponds to at least one of the reproduction speakers within the actual reproduction environment, characterized in that: the metadata associated with each audio object includes an audio object position, and speaker zone constraint metadata indicating whether rendering the respective audio object involves imposing speaker zone constraints, and wherein rendering the respective audio object depends on the audio object position, and includes imposing speaker zone constraints in response to the speaker zone constraint metadata. the metadata associated with each audio object includes an audio object position, and speaker zone constraint metadata indicating whether rendering the respective audio object involves imposing speaker zone constraints, and wherein rendering the respective audio object depends on the audio object position, and includes imposing speaker zone constraints in response to the speaker zone constraint metadata.