Apparatus for mixing at least two audio signals, at least one audio signal associated with at least one parameter, and at least one second audio signal further associated with at least one second parameter, wherein the at least one audio signal and the at least one second audio signal are associated with a sound scene and wherein the at least one audio signal represent spatial audio capture microphone channels and the at least one second audio signal represents an external audio channel separate from the spatial audio capture microphone channels, the apparatus comprising: a processor configured to generate a combined parameter output based on the at least one second parameter and the at least one parameter; and a mixer configured to generate a combined audio signal with a same number or fewer number of channels as the at least one audio signal based on the at least one audio signal and the at least one second audio signal, wherein the combined audio signal is associated with the combined parameter.