Blues and Song Form

In a blues song with a sung text, the lyrics consist of a line that is repeated, then followed by a contrasting line (aab). The melody often follows this structure as well. Blues melodies often leave large gaps to allow for call-and-response between the melodic instrument and other instruments. The blues scale is like a minor pentatonic scale with an additional chromatic passing tone: do–me–fa–fi–sol–te (^1−↓^3−^4−↑^4−^5−↓^7)(1^−↓3^−4^−↑4^−5^−↓7^)(\hat1-\downarrow\hat3-\hat4-\uparrow\hat4-\hat5-\downarrow\hat7). The blues scale can be rotated to begin on its second note, creating a major blues scale: do–re–ri–mi–sol–la (^1−^2−↑^2−^3−^5−^6)(1^−2^−↑2^−3^−5^−6^)(\hat1-\hat2-\uparrow\hat2-\hat3-\hat5-\hat6).

Another essential part of blues phrase structure is the notion of call-and-response, a feature likely inherited from the work songs of enslaved Africans and African Americans. The vocal, lyricized melody takes on the role of the “call” while an instrumental filler takes on the role of the “response.” Notice that in “Gulf Coast Blues,” each lyric labeled with an a is sung entirely and exclusively in the first two measures of the phrase. Example 3 annotates a transcription of “Gulf Coast Blues” to show this call-and-response relationship.

The poetic structure: it is undoubtedly a structure made of three lines of fourbars each but its organization differs on the levels of prosody, melody, andharmony.The prosodic structure: AAB generally. The phrase (either sung or spoken)during the first line is repeated in the second line and a second phrasefollows in the third line.9The melodic structure: AAB but often AA’B. The same melodic phrase usuallyis repeated but may be subject to variation.The harmonic structure: ABC. As seen above, the three lines have been differentfrom each other right from the most original chord changes. The first linestarts with I, the second with IV, and the third with V