Basic Types

Periodic vibration in Hertz.

Example Usage

let nice = Frequency(440.0) // => "a 440"
let mean: Frequency = 440.0 // => "a 440"

Floating point analog to the MIDI note number.

Similarly to the MIDI note number, middle c is represented as 60. Each octave is represented by a distance of 12, thus 48 is the c below middle c, and 72 is the c above middle c.

Example Usage

let warm = NoteNumber(60)
let cold: NoteNumber = 60

The quality of a sound governed by the rate of vibrations producing it.

A Pitch is represented by a NoteNumber value. If offers an interface to represent this NoteNumber as a Frequency given different tuning conventions.

Example Usage

let middle = Pitch(60) // => middle c
let high = Pitch(84) // => two octaves above middle c
let lower = Pitch(69) // => a 440

Ordered sequence of pitch intervals.

A Scale may or may not be octave invariant, and it may or may not be infinitely protracting.

Example Usage

let cMajor: Scale = [0,2,4,5,7,9,11]
let cSharpWholeTone = Scale(1, [2,2,2,2,2,2])
let gHarmonicMinor = Scale(7, .harmonicMinor)

Collection of pitches.

Example usage

let cMajor: Chord = [60,64,67]
let gMinor: Chord = [67,70,74]