This research can be considered as one of the studies that seek to explore, in an argumentative way, subtle and solid philosophical concepts in the field of art. The paper provides an analysis of the concept of “extension” in music as one of the most thought-provoking philosophical concepts. The analysis is carried out by interpreting Ibn-Sina’s special conception of musical extension to answer a fundamental question: given that, unlike other arts, music does not use determinate raw materials to create form, and is only related to sounds, and is perceived by hearing, can it be considered as an extended entity? And if so, what components and characteristics does this musical extension depend on? And how can such extension realize itself in music? This study investigates the issue by adopting the method of mental modeling and utilizing qualitative research methods such as structural analysis and structural deconstruction. The study concludes that based on the auditory perception, and despite the lack of a determinable physical form, a range of potential forms of extension can be realized in music. Such realizable extensional forms include a linear-one-dimensional model (horizontal extension of monophonic sounds), a linear-two-dimensional model (horizontal extension of polyphonic sounds), and the spiral-multidimensional model (horizontal and vertical extension of polyphonic sounds).