Seventh chords add depth and texture to many classic songs due to their interval qualities.
A seventh chord combines a major triad with an added major 7th note to form a unique sound and feel. There are four categories of seventh chords: Major, Minor, Dominant and Diminished chords that each provide their own musical personality.
Major
The major chord is one of the most versatile and common guitar chords you will come across, being capable of being played multiple ways with different fingering on each string and providing a solid basis for learning other chords.
An easy way to build a major chord is through creating a triad. A triad is made up of three notes separated by intervals that produce specific tones – this same effect applies for major triads too!
As an illustration, let us use a C major triad to show how to form chords on the guitar. The root note serves as the lowest note while third and fifth notes make up the remainder of this chord.
Next, examine the intervals between these notes. C to E is considered major; C to G minor; B to F diminished.
Minor
Addition of the seventh note to a basic triad creates an additional texture, creating a mellow and relaxed ambience. This chord type is known as a minor seventh chord (m7) and can be played across various musical genres including classical.
To create a minor seventh chord on guitar, bar all strings with your first finger at the fifth fret before moving your second finger down to the fourth string and tucking it under the third string.
Another method of creating a minor seventh chord is by adding the major sixth interval to an A minor chord and creating a B minor seventh. Or you could add a major seventh to an E minor chord and form a D minor seventh. These chords can serve as the basis of song melodies – perfect for beginners to start learning!
Dominant
A dominant seventh chord is an integral component of many classic rock and blues songs, often serving as its anchor point. These chords don’t fall under either major (with its brighter sound) or minor categories – instead they combine both sounds for maximum effect.
Dominant seventh chords feature a flat 7th note at their root to add a bluesy sound, making for an engaging chord sound with a vibrant brightness that works particularly well in blues music – Carl Perkins famously used two C7 chords on his 1956 hit “Blue Suede Shoes” to craft its infectious tune and toe-tapping melody.
A dominant seventh chord’s notes can also be used to form other types of guitar chords. Chords with more than six notes may be reduced by dropping unnecessary ones, enabling new chords while keeping their original harmony. Some popular altered dominant voicings include G7, A7 and B7 which will expand your chord repertoire significantly.
Half-Diminished
A half-diminished chord, also referred to as a minor seventh flat five (m7b5), can be created by adding a minor seventh to a diminished seventh shape and double flattening it. Though this might seem counterintuitive, this quirk comes down to music theory’s odd definitions of notes and intervals.
If you already know a major, minor or dominant seventh chord, creating a half-diminished variation is straightforward: simply bar both fourth and fifth strings with your pointer finger and middle finger and lower the fifth by one minor third (two frets). So the result will be Eb.
As with the major, minor and dominant seventh chords, half-diminished seventh chords can add tension or resolution in any progression, acting as passing chords between main chords.