The tonic is the first note of a musical scale, and in the tonal method of music composition it is extremely important. The triad formed on the tonic note, the tonic chord, is thus the most important chord. More generally, the tonic is the pitch upon which all other pitches of a piece are hierarchically centered.

In western European tonal music of the 18th and 19th centuries, the tonic center was the most important of all the different tone centers which a composer used in a piece of music, with most pieces beginning and ending on the tonic, usually travelling to the dominant (the fifth above the tonic, or the fourth note up from the tonic) in between.

There can be major scales and minor scales. The tonic remains the same in these two different "modes," for a given key, wheareas scale degrees such as the third degree and the sixth degree are altered in the minor scale.

Howevever, this can be seen another way. Each Minor scale uses exactly the same set of notes (key signature) as some Major scale and vice-versa. The only difference is which of these notes is the tonic. For example, C major and A minor have no sharps or flats. Consequently, the tonic plays an important part in determining why music composed in a minor scale sounds different from music composed in a major scale.

A tonic may be considered a tonal center, while a pitch center functions referentially or contextually in an atonal context, often acting as axis or line of symmetry in an interval cycle (Samson 1977). Pitch centricity was coined by Arthur Berger in his "Problems of Pitch Organization in Stravinsky".

See also

• Tonal music
• Dominant
• Mediant
• Supertonic
• Subdominant
• Final (music)

Source

• Samson, Jim (1977). Music in Transition: A Study of Tonal Expansion and Atonality, 1900-1920. New York: W.W. Norton & Company. ISBN 0393021939.