What Are Keynotes and Tonics?

The First Notes of Musical Scales

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When reading sheet music and playing an instrument, it's important to understand the overall key of the song, and you can usually look at the last note of a piece of music to find its keynote. The keynote is defined as the first note of a musical scale upon which a musical piece's tonal progression is based.

Keynotes are also known as tonic in English, tonica in Italian, tonique in French, and tonika in German, but should not be confused with key signatures, which are the flats and sharps that appear at the beginning of measures to denote which notes will be played higher or lower than their normal pitch for the duration of the signature — with the exception of accidentals, which carry through individual measures.

Keynotes designate the names of musical scales, and although the note that ends a particular song will often also be the keynote of that piece of music, it's the overall melody, tone, and variety of key signatures that determine the keynote of a musical arrangement — in an A# (sharp) minor scale, A# is the keynote, and in D major scale, the keynote is D.

Common Keynotes in Music

Although there are a number of rare and theoretical music keys, most of these are not used in modern compositions because the number of accidentals required to pull off something like a B# major scale would render the sheet music too complicated to quickly read and play.

The most common keynotes include C, F, and E major and minor scales and the B flat major and minor scales. However, the most common of these is definitely the C major scale, which is used across all forms of classical, pop, rock, and country music.

Not to be confused with root notes, which designate the note of a chord, keynotes are the basis for entire arrangements, so while you may be learning individual chords on the guitar or piano that vary greatly, you will mostly be working in the C, F, or E scales for playing traditional and modern arrangments of music.

Function of Keynotes in Music

Like keynote speeches, which deliver a message centered around an extremely specific topic, keynotes center songs around a specific musical note and build up and down the scale from there, creating a central melody to the piece that inspires listeners to have a concern from the piece itself.

Essentially, most popular music is composed with a sense of harmony within the arrangement of the chords and notes, and in that sense, a keynote defines the tone of a musical arrangement by setting the starting and ending point for the piece to progress through, and each chord or tone within the piece acts as it relates to that keynote.

For these reasons, you'll typically find the last note of an arrangement — especially from the late 18th and 19th centuries and many folk songs of today — is the keynote as it provides a nice finishing point for the narrative of the song. However, if the keynote isn't the last note, you can also listen to the piece and try to determine which pitch and note the other chords are all trying to relate to.