An audio rendering method and computer readable medium instructions, comprising obtaining sound object data for a sound object in a first format suitable for rendering into an output signal and obtaining user tracking information for a user at a time subsequent to setting up the sound object data in the first format. The sound object is rendered by converting the sound object data from the first format into the output signal and in conjunction with said rendering a transform is applied to the sound object, wherein the transform depends on the user tracking data. Two or more speakers are driven using the output signal.