In music

Music

Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...

 or music theory

Music theory

Music theory is the study of how music works. It examines the language and notation of music. It seeks to identify patterns and structures in composers' techniques across or within genres, styles, or historical periods...

, the supertonic is the second degree

Degree (music)

In music theory, a scale degree or scale step is the name of a particular note of a scale in relation to the tonic...

 or note of a diatonic scale

Diatonic scale

In music theory, a diatonic scale is a seven note, octave-repeating musical scale comprising five whole steps and two half steps for each octave, in which the two half steps are separated from each other by either two or three whole steps...

, one step

Major second

In Western music theory, a major second is a musical interval spanning two semitones, and encompassing two adjacent staff positions . For example, the interval from C to D is a major second, as the note D lies two semitones above C, and the two notes are notated on adjacent staff postions...

 above the tonic. In music theory

Music theory

Music theory is the study of how music works. It examines the language and notation of music. It seeks to identify patterns and structures in composers' techniques across or within genres, styles, or historical periods...

, the supertonic chord is symbolized by the Roman numeral ii in a major scale, indicating that the chord is a minor chord

Minor chord

In music theory, a minor chord is a chord having a root, a minor third, and a perfect fifth.When a chord has these three notes alone, it is called a minor triad....

 (for example, D-F-A in C major), or ii in a natural minor scale, indicating that the chord is a diminished chord

Diminished chord

A diminished triad chord or diminished chord is a triad consisting of two minor thirds above the root — if built on C, a diminished chord would have a C, an E and a G. It resembles a minor triad with a lowered fifth....

 (for example, D-F-A in C natural minor), if in second inversion a six-four chord

Inversion (music)

In music theory, the word inversion has several meanings. There are inverted chords, inverted melodies, inverted intervals, and inverted voices...

 (Ab-D-F), and if the third is raised an augmented sixth chord

Augmented sixth chord

In music theory, an augmented sixth chord contains the interval of an augmented sixth above its "root" or bass tone . This chord has its origins in the Renaissance, further developed in the Baroque, and became a distinctive part of the musical style of the Classical and Romantic periods.-Resolution...

 (A-F). If in major or minor, through the lowering of the second scale degree (also the sixth in major), the chord is major (D-F-A) then it is a Neapolitan 6th chord

Neapolitan chord

In music theory, a Neapolitan chord is a major chord built on the lowered second scale degree. It most commonly occurs in first inversion so that it is notated either as II6 or N6 and normally referred to as a Neapolitan sixth chord...

, N⁶ or II⁶. The supertonic may be raised as part of the common-tone diminished seventh chord, ii⁷.
One variant of the supertonic seventh chord is the supertonic diminished seventh with the raised supertonic, which equals the lowered third through enharmonic equivalence (in C: D=E).

Predominant chords are chords which distinguish chord V as a goal of motion (as opposed to it acting as an embellishing chord within a phrase) they create gravity and harmonic motion towards dominant harmony, and form a fundamental aspect of western tonal music.

The supertonic chord is known as a predominant chord, as it is one of the unique chords which has a natural tendency to gravitate towards chord V and strengthen V as a goal of motion. The supertonic chord lies a fifth above chord V. Descending fifths are a strong basis for harmonic motion and harmonic motion through intervals of fifths is a natural way for chords to progress to one another; the supertonic is one of the strongest pre-dominants and approaches chord V from above through a descending 5th. It is preferable to avoid chord two in root position in the minor mode due to the harsh quality of its diminished intervals, ii6 is a much nicer alternative. This is less of an issue if the chord contains a chordal seventh; indeed, root-position diminished seventh chords are quite common.

Adding a chordal seventh to the supertonic (minor or diminished) does nothing to interfere with its predominant qualities, but rather intensifies their predominant function and also increases harmonic intensity and motion towards dominant harmony. Supertonic seventh chords are such intense predominant chords because they outline the leading note contained in chord V with a dissonance.

"Supertonic" also refers to a relationship of musical keys. For example, relative to the key of C major, the key of D major (or D minor) is the supertonic. Modulation

Modulation (music)

In music, modulation is most commonly the act or process of changing from one key to another. This may or may not be accompanied by a change in key signature. Modulations articulate or create the structure or form of many pieces, as well as add interest...

 (change of key) to the supertonic is relatively common (by far the most common modulation in modern popular music

Popular music

Popular music belongs to any of a number of musical genres "having wide appeal" and is typically distributed to large audiences through the music industry. It stands in contrast to both art music and traditional music, which are typically disseminated academically or orally to smaller, local...

), though in classical music

Classical music

Classical music is the art music produced in, or rooted in, the traditions of Western liturgical and secular music, encompassing a broad period from roughly the 11th century to present times...

 it is more common to modulate to the dominant

Dominant (music)

In music, the dominant is the fifth scale degree of the diatonic scale, called "dominant" because it is next in importance to the tonic,and a dominant chord is any chord built upon that pitch, using the notes of the same diatonic scale...

 or other keys.

In German theory derived from Hugo Riemann

Hugo Riemann

Karl Wilhelm Julius Hugo Riemann was a German music theorist.-Biography:Riemann was born at Grossmehlra, Schwarzburg-Sondershausen. He was educated in theory by Frankenberger, studied the piano with Barthel and Ratzenberger, studied law, and finally philosophy and history at Berlin and Tübingen...

, the supertonic is considered the subdominant parallel

Subdominant parallel

In music theory, the subdominant parallel is the relative to the subdominant and is thus considered to have or fulfill the function of the subdominant. The term is derived from German theory and the writings of Hugo Riemann....

: Sp/T in major though sP/T in minor (AM).