Chords are an integral component of any song. They set the atmosphere, evoking emotions and creating tension which is resolved through shifting harmony lines.
As chords can make or break a song, understanding their function within each key is of great importance. Mismatched chords may result in unintended dissonance and disjointment from an otherwise perfect song.
Major
Major chords are composed of all twelve tones of a major scale and have the greatest sense of completion and permanence; therefore they make for a powerful foundation in songs with progressive progressions, providing strong support for any additional chords that might follow later.
You have probably encountered I, IV and V chords before in songs by artists like Bob Dylan (Knocking on Heaven’s Door) or Guns ‘n Roses (Sweet Child O’ Mine). Both are in G major while its IV and V chords in C major have similar intervals derived from one major scale scale (see chart below). You’ll likely recognize them from songs by these acts like Knocking on Heaven’s Door by Bob Dylan and Guns ‘n Roses (Sweet Child O’ Mine). These chords can also be heard in songs such as Bob Dylan (Knocking on Heaven’s Door) and Guns N Roses’ Sweet Child O Mine by Guns N Roses). These all share similar notes; in terms of being derived from one major scale scale with identical intervals between notes (see chart below).
A major is an extremely versatile key, used across various genres of music. Although less frequently seen in classical pieces than keys with fewer sharps and flats, A major was Mozart’s favorite key for clarinets; moreover it often appears in chamber music such as Mendelssohn and Beethoven symphonies.
It is a highly melodic key, creating beautiful soundscapes when played by most instruments, as well as having an expansive tone perfect for orchestral builds and crescendos. Furthermore, this key can also be found frequently used in folk and pop songs, since its sound matches up perfectly with most vocal ranges.
As with major keys, all intervals between notes are equivalent in minor keys as well. Therefore, most chords that are used in one major key will also appear in its relative minor key – though these chords often feature lessened and unstable tones due to having intervals that have been flattened by half-steps.
To visualize this difference between major and minor chords, try playing a C major triad and then moving all your fingers one white note up towards the right. Notice how two notes move two semitones upward (C to D), while another moves by a full step (C to E). These changes make major chords distinct from minor ones.
Minor
Minor keys offer the ideal environment for exploring triads and seventh chords, making the minor scale an excellent way to explore them. While one might assume that minor would limit chord possibilities, this is not true: minor has the same triad chords as major with one note lower in second inversion than their first inversion, creating distinctive sounds from these chords.
Minor key chord progressions can range from soothing (George Gershwin’s “Summertime”), funky (the Commodores’ “Brick House”) or rocking (Dire Straits’ “Sultans of Swing”). Whatever style of music you enjoy playing in a minor key, its chord progressions should always be part of your repertoire.
A typical method for building songs in the minor key, using chord progressions such as i – iv – v, is often employed when writing in that key. Other possibilities exist, however; other progressions could include using something like i – bVII – bVII to add interest. When dealing with minor chords, typically minor triads and major seventh chords comprise these progressions while vi is an all major seventh chord; with major seventh chords the vi provides major seventh harmony chord. bVII chord is used to add bright contrast with its dark minor tonic; think of its shine against its dark presence–without negating its darkness but making itself known.
If you want to change a minor chord into a major one, simply raise its third degree. This simple method helps remember that major and minor chords are opposites.
The minor scale has three forms, known as natural minor, harmonic minor and melodic minor scales. Each forms different chords in a minor key with differing ascending and descending patterns – for instance the natural minor’s “IV chord” corresponds to a minor triad whereas it takes on different characteristics in harmonic minor; an “iv chord” in natural minor is typically composed of minor seventh chords (iiv, IV, VI etc).
Dominant
A dominant seventh chord features an unsettling sound and can be found in blues, jazz, rock and funk music. This tension stems from dissonance between its flat seventh and third in the chord; this dissonance often creates tension which is relieved when resolved by tonic chord. Thus it forms an essential element of most cadence progressions.
A dominant seventh chord can be formed using any scale degree; however, its most frequent location is on the fifth scale degree of a major or minor scale (pictured on the right in this example). Also referred to as V7 or viiom chord, its Roman numeral designation might include G7 (the G represents C major’s fifth scale degree).
Dominant seventh chords are commonly enhanced with an augmented chord, a combination of a dominant seventh and major triad, adding minor third and perfect fifth notes to give a fuller, richer sound while still sounding dominant. Augmented chords have long been used in popular songs as dramatic arrangements to give their songs that special edge.
Dominon seventh chords play an essential part in both cadence progressions and modulations of harmonic direction and modulation. Because these chords tend to move toward the tonic chord, it makes them ideal to use at the conclusion of sections or cadences; additionally, their strong tension created by their seventh note makes them suitable for introducing new keys or harmonic modalities.
The dominant seventh is an essential building block of various other chords, including diminished and augmented chords, which can help create an array of sounds and styles within music.
The dominant seventh chord is essential in understanding key harmony. Understanding its various forms will enable you to write your own chords more easily as well as help compose bass lines or play rhythm guitar rhythmically.
Suspended
Chord progressions add texture and intrigue to a song by incorporating various types of chords. While it’s straightforward to expand basic major and minor chords with seventh notes, some musicians also employ suspended chords as an additional way to build tension and anticipation in a performance.
A sus chord is a triad that lacks its third interval, the note which distinguishes major and minor chords. Without this third note defining major and minor tones, sus chords have an ambiguous sound and have several forms; sus2 chords feature perfect fourth in place of third for dissonant sound without easily being resolved into consonant chords; sus4 chords include major second as third instead for even greater dissonance which doesn’t easily resolve into either major or minor tones.
Sus2 and sus4 chords are most often employed, although it isn’t uncommon to encounter seventh or ninth suspended chords as well. While they lack the ambiguous quality associated with sus2 or sus4 chords, these suspended chords still serve to create tension and anticipation within a song.
Suspended chords in songs can be an effective way to enhance the lyrical content, especially if they appear near the end of phrases or bars. Gnarls Barkley’s song “Crazy” uses this technique in the chorus with a sus 4 to G chord, giving an illusion that its chorus has taken off into space before returning back down into earthly tune.
One disadvantage of sus chords is their incompatibility with other chords in a song’s key; without its third note present, a sus chord feels incomplete and uncertain of where it wants to go. Therefore, it should only be used sparingly and when appropriate in progressions.