Eight-bar blues

In music, an eight-bar blues is a typical blues chord progression, "the second most common blues form," "common to folk, rock, and jazz forms of the blues," taking eight 4/4 or 12/8 bars to the verse.

Examples include "Sitting on Top of the World" and "Key to the Highway", "Trouble in Mind" and "Stagolee". "Heartbreak Hotel", "How Long Blues", "Ain't Nobody's Business", "Cherry Red", and "Get a Haircut" are all eight-bar blues standards.

One variant using this progression is to couple one eight-bar blues melody with a different eight-bar blues bridge to create a blues variant of the standard 32-bar song. "Walking By Myself", "I Want a Little Girl" and "(Romancing) In The Dark" are examples of this form. See also blues ballad.

Eight bar blues progressions have more variations than the more rigidly defined twelve bar format. The move to the IV chord usually happens at bar 3 (as opposed to 5 in twelve bar). However, "the I chord moving to the V chord right away, in the second measure, is a characteristic of the eight-bar blues."

In the following examples each box represents a 'bar' of music (the specific time signature is not relevant). The chord in the box is played for the full bar. If two chords are in the box they are each played for half a bar, etc. The chords are represented as scale degrees in Roman numeral analysis. Roman numerals are used so the musician may understand the progression of the chords regardless of the key it is played in.

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