Yamaha PSR-I425

Style (Auto-accompaniment) Functions

PSR-I425 Owner’s Manual 75

Two or more notes played together constitute a “chord”.

The most basic chord type is the “triad” consisting of three notes: the

root, third, and ﬁfth degrees of the corresponding scale. A C major triad,

for example, is made up of the notes C (the root), E (the third note of the

C major scale), and G (the ﬁfth note of the C major scale).

In the C major triad shown above, the lowest note is the “root” of the

chord (this is the chord’s “root position” ... using other chord notes for

the lowest note results in “inversions”). The root is the central sound of the chord, which supports and

anchors the other chord notes.

The distance (interval) between adjacent notes of a triad in root position is either a major or minor third.

The lowest interval in our root-position triad (between the root and the third) determines whether the triad

is a major or minor chord, and we can shift the highest note up or down by a semitone to produce two addi-

tional chords, as shown below.

The basic characteristics of the chord sound remain intact even if we change the order of the notes to create

different inversions. Successive chords in a chord progression can be smoothly connected, for example, by

choosing the appropriate inversions (or chord “voicings”).

● Reading Chord Names

Chord names tell you just about everything you need to know about a chord

(other than the inversion/voicing). The chord name tells you what the root of the

chord is, whether it is a major, minor, or diminished chord, whether it requires a

major or ﬂatted seventh, what alterations or tensions it uses ... all at a glance.

● Some Chord Types (These are just some of the “Standard” chord types recognized by the PSR-I425.)

Chord Basics

3rd 3rd

Root

Major third–four half steps (semitones) Minor third–three half steps (semitones)

CMCmCaug Cdim

Major chord

Minor 3rd Major 3rd Major 3rd Minor 3rd Major 3rd Major 3rd Minor 3rd Minor 3rd

Minor chord Augmented chord Diminished chord

Root note Chord type

Csus4 C7Cm7 CM7

(b5)Cm7

(b5)C7sus4

CmM7

Perfect 5 th Perfect 4 th Flatted 7 th Major chord Flatted 7 th Minor chord Major 7 th Major chord

Major 7 th Minor chord Flatted 5 th 7 th chord Flatted 5 th Minor 7 th chord Flatted 7 th Suspended

4 th chord

Suspended 4 th 7 th Minor 7 th Major 7 th

7 th, suspended 4 th

Minor 7 th, ﬂatted 5 th

7 th, ﬂatted 5 th

Minor/major 7 th