An added tone chord, or added note chord, is a non-tertian chord composed of a triad and one or more extra "added" notes. Any tone that is not a seventh is commonly categorized as an added tone. It can be outside the tertian sequence of ascending thirds from the root, such as the added sixth or fourth, or it can be in a chord that does not consist of a continuous stack of thirds, such as the added thirteenth (six thirds from the root, but the chord does not have the previous tertian notes – the seventh, ninth or eleventh). The concept of added tones is convenient in that all notes may be related to familiar chords.
Inversions of added tone chords where the added tone is the bass note are usually simply notated as slash chords instead of added tone chords. For example, instead of C<sup>add2</sup>/D, just C/D is used.
An added tone such as fourth voiced below the root may suggest polytonality. The practice of adding tones may have led to superimposing chords and tonalities, though added tone chords have most often been used as more intense substitutes for traditional chords.An added second chord (or add2 chord) or added ninth chord (or add9 chord) is a major or minor triad with the note a major second or major ninth, respectively, above the root. For example, the add2 chord built on C, notated as C<sup>add2</sup>, has pitches C–D–E–G:
: <score sound="">
{
\override Score.TimeSignature
- 'stencil = ##f
\relative c' {
\time 4/4
\set Score.tempoHideNote = ##t \tempo 1 = 20
<c d e g>1
}
}
</score>
Since this is the same pitch class, the difference is the voicing of the added note within the chord.
Examples in popular music include The Rolling Stones' "You Can't Always Get What You Want", Mr. Mister's "Broken Wings", Don Henley's "The End of the Innocence", The Police's "Every Breath You Take", Cheap Trick's "The Flame", Lionel Richie's "All Night Long (All Night)", Men at Work's "It's a Mistake", DeBarge's "Rhythm of the Night", Starship's "We Built This City", Deniece Williams' "Let's Hear It for the Boy", The jazz rock group Steely Dan popularized a particular voicing of the add2 chord they dubbed the mu chord.
Added fourth chord
An added fourth chord (or add4 chord) is a major or minor triad with the note a perfect fourth above the root. For example, the add4 chord built on C, notated as C<sup>add4</sup>, has pitches C–E–F–G:
: <score sound="">
{
\override Score.TimeSignature
- 'stencil = ##f
\relative c' {
\time 4/4
\set Score.tempoHideNote = ##t \tempo 1 = 20
<c e f g>1
}
}
</score>
Add4 chords almost always are almost always built on the fifth scale degree where the added note is the key's tonic note. Examples in popular music include the second chord in the verse of "Runaway Train" and the introduction of The Who's "Baba O'Riley".
6/9 chord
A 6/9 chord is a major triad with the notes a major sixth and major ninth above the root. For example, the 6/9 chord built on C, notated as C<sup>6/9</sup>, has pitches C–E–G–A–D:
: <score sound="">
{
\override Score.TimeSignature
- 'stencil = ##f
\relative c' {
\time 4/4
\set Score.tempoHideNote = ##t \tempo 1 = 20
<c e g a d>1
}
}
</score>
It is not a tense chord requiring resolution and is considered a substitute for the tonic in jazz.
The minor 6/9 chord is a minor triad with an added sixth and ninth, evoking the Dorian mode and is also suitable as a minor tonic in jazz.
Mixed third chords
A mixed third chord (also split-third chord) includes both the major and minor thirds (e.g. C–E–E–G), although the thirds are usually separated by an octave or more.