Abstract: Embodiments of the present invention relate to a user interface apparatus, method and computer program for composing an audio output file, the user interface apparatus including: an arrangement of interactively operable visual elements displayed on display means, each visual element represents an instrument content block, and each instrument content block comprises musical content sub-blocks from a musical instrument and has a plurality of audio parameters, wherein an instrument content block is activated by a user tapping the corresponding visual element with pointing means, and whereby, when an instrument content block is activated by a user one or more of a plurality of interactive authoring tools are provided to enable the user to adjust audio parameters of the activated instrument content block, and the audio parameters adjusted by the user are applied to the instrument content block, and means for combining the instrument content blocks to generate the audio output file.

Abstract: Techniques described herein provide a computer implemented system, method and computer program for generating an audio output file, the method including steps of: selecting a subset of instrument content blocks from a group of instrument content blocks by determining a musical style for the audio output file, in which the musical style is configured with a plurality of musical slots and each slot is associated with a predetermined musical rule, using the predetermined musical rule for each slot to select a musical template from a plurality of musical templates for the slot, in which the selected musical template defines a chord progression of successive musical chords at a musical key and tempo, selecting for each slot an instrument content block that matches the chord progression defined by the selected musical template, and generating the audio output file by combining the subset of instrument content blocks.