A method of playing back a multichannel audio signal via a playback device having a plurality of loudspeakers (2-1,..., 2-N), said loudspeakers being arranged at fixed locations of the playback device and defining a spatial window for playing back sound relative to a "reference" spatial position (Pref), said playback method comprising: • a spatial analysis step (▪I) of spatially analyzing the multichannel audio signal, this step comprising: • extracting at least one sound object from the signal; and • for each extracted sound object, estimating a diffuse or localized nature of this sound object, and estimating a position of this sound object relative to the sound playback spatial window of the playback device; said method being characterized by: • a playback step (▪II, E50, E51, E52, E53) of playing back the audio signal via the plurality (2-1,..., 2-N) of loudspeakers of the playback device, during which step, playback treatment (T-A1, T-A2, T-B, T-C) is applied to each sound object extracted from the audio signal for playing that object back via at least one loudspeaker of the plurality of loudspeakers of the playback device, this playback treatment depending on the diffuse or localized nature of the sound object and on its position relative to the sound playback spatial window as estimated during the spatial analysis step; the playback treatment (T-B, T-C) including creating at least one virtual source (11, 12) outside the playback spatial window of the playback device, from the loudspeakers of the playback device, whenever the sound object is estimated during the spatial analysis step as being diffuse or as being positioned outside the playback spatial window of the playback device. • a spatial analysis step (▪I) of spatially analyzing the multichannel audio signal, this step comprising: • extracting at least one sound object from the signal; and • for each extracted sound object, estimating a diffuse or localized nature of this sound object, and estimating a position of this sound object relative to the sound playback spatial window of the playback device; said method being characterized by: • extracting at least one sound object from the signal; and • for each extracted sound object, estimating a diffuse or localized nature of this sound object, and estimating a position of this sound object relative to the sound playback spatial window of the playback device; • a playback step (▪II, E50, E51, E52, E53) of playing back the audio signal via the plurality (2-1,..., 2-N) of loudspeakers of the playback device, during which step, playback treatment (T-A1, T-A2, T-B, T-C) is applied to each sound object extracted from the audio signal for playing that object back via at least one loudspeaker of the plurality of loudspeakers of the playback device, this playback treatment depending on the diffuse or localized nature of the sound object and on its position relative to the sound playback spatial window as estimated during the spatial analysis step; the playback treatment (T-B, T-C) including creating at least one virtual source (11, 12) outside the playback spatial window of the playback device, from the loudspeakers of the playback device, whenever the sound object is estimated during the spatial analysis step as being diffuse or as being positioned outside the playback spatial window of the playback device.