An apparatus for spatial audio signal decoding associated with a plurality of speaker nodes placed within a three-dimensional space, the apparatus configured to: receive at least one associated audio signal, the associated audio signal based on a defined speaker layout audio signal; spatial metadata associated with the associated audio signal; at least one parameter representing a defined speaker layout associated with the defined speaker layout audio signal; and at least one parameter representing an output speaker layout; synthesize from the at least one associated audio signal at least one output audio signal based on the spatial metadata and the at least one parameter representing the defined speaker layout and the at least one parameter representing an output speaker layout, wherein the apparatus, when configured to synthesize from the at least one associated audio signal at least one output audio signal based on the spatial metadata and the at least one parameter representing the defined speaker layout and the at least one parameter representing an output speaker layout, is further configured to: divide the at least one associated audio signal into a direct part and diffuse part based on the spatial metadata; synthesize a direct audio signal based on the direct part of the at least one associated audio signal; synthesize a diffuse audio signal based on the diffuse part of the at least one associated audio signal; and combine the direct audio signal and diffuse audio signal to generate the at least one output audio signal, wherein at least one of the synthesis of the direct audio signal and/or synthesis of the diffuse audio signal is based on the at least one parameter representing the defined speaker layout and the at least one parameter representing an output speaker layout. receive at least one associated audio signal, the associated audio signal based on a defined speaker layout audio signal; spatial metadata associated with the associated audio signal; at least one parameter representing a defined speaker layout associated with the defined speaker layout audio signal; and at least one parameter representing an output speaker layout; synthesize from the at least one associated audio signal at least one output audio signal based on the spatial metadata and the at least one parameter representing the defined speaker layout and the at least one parameter representing an output speaker layout, wherein the apparatus, when configured to synthesize from the at least one associated audio signal at least one output audio signal based on the spatial metadata and the at least one parameter representing the defined speaker layout and the at least one parameter representing an output speaker layout, is further configured to: divide the at least one associated audio signal into a direct part and diffuse part based on the spatial metadata; synthesize a direct audio signal based on the direct part of the at least one associated audio signal; synthesize a diffuse audio signal based on the diffuse part of the at least one associated audio signal; and combine the direct audio signal and diffuse audio signal to generate the at least one output audio signal, wherein at least one of the synthesis of the direct audio signal and/or synthesis of the diffuse audio signal is based on the at least one parameter representing the defined speaker layout and the at least one parameter representing an output speaker layout. divide the at least one associated audio signal into a direct part and diffuse part based on the spatial metadata; synthesize a direct audio signal based on the direct part of the at least one associated audio signal; synthesize a diffuse audio signal based on the diffuse part of the at least one associated audio signal; and combine the direct audio signal and diffuse audio signal to generate the at least one output audio signal, wherein at least one of the synthesis of the direct audio signal and/or synthesis of the diffuse audio signal is based on the at least one parameter representing the defined speaker layout and the at least one parameter representing an output speaker layout.