Fourpitchclass

Fourpitchclass is a term used in music theory to describe a set of four distinct pitch classes within an octave. A pitch class represents a single note name, ignoring its octave designation. For example, C, C#, and Db are all members of the pitch class C. When discussing a set of four pitch classes, the specific intervallic relationships between these pitches are crucial. These relationships determine the character and harmonic implications of the collection.

The concept of pitch class sets is fundamental to atonal and serial music, where traditional notions of key and harmony are often absent. Analyzing these sets allows musicians and theorists to understand the underlying structure and organization of music that does not adhere to diatonic scales. Fourpitchclass sets can be identified and classified based on their interval content, prime form, and potential for transposition and inversion. Different fourpitchclass sets can sound very different due to their unique intervallic makeup. For instance, a set composed of closely spaced pitches will have a different sonic quality than one with widely separated pitches. The study of these sets helps to reveal the sophisticated compositional techniques employed by composers in various musical styles.