Schenker more than once refers to what he calls Klang or Klang der Natur, the « sound of nature », the complex sound formed of its harmonic partials (see particularly Harmonielehre, § 8 ff; Naturklang is found in Der freie Satz, §§ 1, 7, 9). It is not that he seeks to endow music with a natural or scientific foundation, merely that he considers the harmonic series as a model, a suggestion of which the artist has made use to form the notes, the intervals, the scales and the chords. Schenker insists that “the acoustician […] knows how to describe this phenomenon exactly and without flaw. He gets on slippery ground, however, as soon as he tries to apply this knowledge to an understanding of art and the practice of the artist. […] It is fortunate, under these circumstances, that the artist, whose grasp is firmer by instinct than by reason, continues to be guided by the former rather than by the latter […]. It is our purpose here to interpret the instinct of the artist and to show what use he had made and is making unconsciously of Nature’s proposition; and how much of it, on the other hand, he has left, and probably will ever leave, unused.” (Harmony, transl. E. Mann Borghese, p. 21.)
Schenker further shows that music makes use only of the notes and the intervals corresponing to the first five harmonic partials and to their multiples, reduced to a limited ambitus, and that the harmonics corresponding to prime numbers starting from the seventh and to their multiples have no musical usage. He stresses also that if the major triad quite closely corresponds to the model proposed by nature, the minor triad on the contrary cannot be justified in the same way, that it fully results from an artistic intention. (Harmonielehre, § 23).
The Klang thus is an abstract idea, that Schenker at least once compares to Platonician ideas (Der Tonwille I, p. 23). This idea must be objectived, realized, to become a real musical work. The primal structure (Ursatz) is its first realization.
Schenker’s conception of the Klang often was misunderstood because one believed that, as most of his contemporaries, he tried to describe a natural foundation for music. A more attentive reading shows that this certainly is not the case.