Chords within a key have an essential function and purpose, being formed from notes from a major scale.
Unless stated otherwise, all chords in a C major scale song will consist of notes taken from its major scale.
These chords, known as diatonic chords, occur naturally in any key.
Major Triads
Triads are a type of chord consisting of three or more notes played at once, typically consisting of root, major third, and perfect fifth pitches. Triads are among the first chords beginners learn to play because they are relatively straightforward and possess an easily recognisable sound.
As you begin learning triads, it is helpful to keep in mind that all triads can be distinguished by their intervals. A major triad will feature a major third between its lowest and middle notes while minor triads typically utilize minor thirds between middle and top notes – these types of chords are known as tertian triads.
Triads in music are usually referred to by their letter name (such as C Major), rather than by their number name. This is because most triads are written with their root note at the bottom and all other notes stacked above it; this arrangement is known as closed spacing, and even when written otherwise (for instance by inversion) such triads may be written this way.
Step one in identifying a triad is looking at the piano diagram above and noting its note positions and interval short names – known as its name at the bottom of the piano diagram.
Once a triad is named, its quality must also be established. These qualities include major, minor, augmented and diminished chord qualities based on its number of tones – for instance a major triad built using do, fa, sol (1 4, and 5 respectively) will always be major regardless of key or key signature; minor triads constructed on re & Ti (2&7) or on O DO and Sao (4 9 + 12) would fall under minor categories while those constructed using O DO + SAO (4, 9, 12) would fall under augmentated categories.
Triad quality is often indicated with the letter representing its root in figured bass notation, though this isn’t necessary; any quality of triad may be represented within any key signature – for instance, below is a C Major but can also be written as Eb or D Major.
Minor Triads
Triads, chords composed of three consecutive notes in order, can be described as triads. Triads form the basic building block for many types of chords and come in five distinct qualities: Major, Minor, Diminished, Augmented and Suspended. Each type has a distinctive sound in music as well as distinct interval patterns that define them further.
Minor triads consist of three elements, including a minor third (m3) on the bottom, major thirds (M3) at either end, and a perfect fifth (P5) between outer notes. Intervals between major and minor thirds are half steps while perfect fifth intervals span whole steps; minor triads are more frequently employed in music than major ones as their fifth chord has more consonant sound qualities.
C major, D minor, E minor, F minor and G minor chords comprise the chords in this key of C major. Only these five triads contain minor third and perfect fifth components; all other triads found herein are dominant or seventh chords.
Each triad in a major key has an assigned number depending on its starting scale degree, such as I (C major). For example, this chart displays it as number 1, because it starts on the tonic note of the scale – though this method also works in minor keys; its use differs only slightly as some chords may feature roman numerals to distinguish variations of one chord from another.
Triads can be inverted to produce different sounds. To invert a chord, simply switch around its notes – instead of beginning on A as its tonic note you begin on C as its second note and move up one octave (12 notes) before returning back down again onto A for the tonic note – this is known as its first inversion.
Each inversion has its own distinct sound and serves a specific purpose; for instance, major seventh chords often add tension to their music by being inverted while minor sevenths are typically left without inversion.
Dominant Triads
The dominant chord is one of the keystones in any key, being defined by its strength and tension. It serves as an excellent way to end a piece or section with, as well as being utilized in cadential progressions. In order to effectively utilize this chord it is vitally important that its connection with its respective key’s tonic triad is understood.
F major, for instance, contains a dominant chord on C which consists of root, third and fifth notes stacked to form a triad, then given their Roman numeral V due to being built upon the fifth scale degree in key. This dominant chord serves as its own tonic by trying to move upward towards it – it makes up part of its dominant nature.
Dominant seventh chords can be extended by lowering their fifth note to create diminished chords, or raising it for major seventh chords, thus expanding their use across different areas of a key. They’re sometimes also known as seventh chords; typically in F major these would be known as viio, ivy and vi. See diagram below.
To create a dominant seventh chord, begin playing from its root note before adding chords and creating a dominant triad. Being constructed on the fifth scale degree will ensure it connects directly to its tonic triad via its root note.
As is well-known, the tonic triad is of paramount importance in any key, so understanding its construction is of utmost importance. Subdominant and dominant chords may also come in handy during progressions using tonic cadences.
Dominant triads are easy to recall because they contain just three notes that all connect on the fifth scale degree of their key signatures, making them easily recognizable even within complex key signatures and giving them an unmistakable sound.
Fifths
The circle of fifths can be an extremely helpful tool for understanding chord progressions and the relationships among different keys. It serves as a visual way of organizing Western music theory’s twelve chromatic pitches into Western scales and chords; seeing their notes laid out as a circle also allows one to recognize how related different keys are, especially those with similar key signatures such as C and G major keys which differ by only one pitch class (whereas major keys with six sharps are distant relative to minor keys without flats and require many accidentals to create).
The circle of fifths can also help you transpose songs between keys. Simply move the chord pattern up or down one perfect fifth as needed – for example if you wish to change from C major to E major you would simply shift up five steps before returning it back down five steps again until reaching the appropriate key.
Use the circle of fifths to explore relationships between relative minor and major key signatures. Each major key has its own relative minor that can be found by going clockwise around the circle of fifths – for instance C major’s relative minor is A minor and so forth.
Understanding the order of flats and sharps when using a circle of fifths is crucial, since their pattern echoes around it. For instance, if a key signature contains seven flats this indicates all notes within its scale will be flats; as soon as you move counterclockwise on the circle from C you will discover new sharps being added in sequence of F, C, G D etc.
Beginning an amateur musical journey can be daunting, so learning to navigate the circle of fifths is an invaluable asset. Not only will it sharpen your ears for chords and progressions, but it will also enable faster transposition between keys.