<P> Jazz guitarists use their knowledge of harmony and jazz theory to create jazz chord "voicings", which emphasize the 3rd and 7th notes of the chord . Unlike pop and rock guitarists, who typically include the root of a chord (even, with many open chords and barre chords, doubling the root), jazz guitarists typically omit the root . Some more sophisticated chord voicings also include the 9th, 11th, and 13th notes of the chord . A typical jazz voicing for the chord G7 would be the individual notes B, E, F, and A . This voicing uses the 3rd (the note B), the 7th (the note F), along with the 6th (the note E) and the 9th (the note A). </P> <P> In some modern jazz styles, dominant 7th chords in a tune may contain altered 9ths (either flattened by a semitone, which is called a "flat 9th", or sharpened by a semitone, which is called a "sharp 9th"); 11ths (sharpened by a semitone, which is called a "sharp 11th"); 13ths (typically flattened by a semitone, which is called a "flat 13th"). </P> <P> Jazz guitarists need to learn about a range of different chords, including major 7th, major 6th, minor 7th, minor / major 7th, dominant 7th, diminished, half - diminished, and augmented chords . As well, they need to learn about chord transformations (e.g., altered chords, such as "alt dominant chords" described above), chord substitutions, and re-harmonization techniques . Some jazz guitarists use their knowledge of jazz scales and chords to provide a walking bass - style accompaniment . </P> <P> Jazz guitarists learn to perform these chords over the range of different chord progressions used in jazz, such as the II - V-I progression, the jazz - style blues progression, the minor jazz - style blues form, the "rhythm changes" progression, and the variety of chord progressions used in jazz ballads, and jazz standards . Guitarists may also learn to use the chord types, strumming styles, and effects pedals (e.g., chorus effect or fuzzbox) used in 1970s - era jazz - Latin, jazz - funk, and jazz - rock fusion music . </P>

How is the guitar displayed in terms of harmony