<P> City or urban blues styles were more codified and elaborate, as a performer was no longer within their local, immediate community, and had to adapt to a larger, more varied audience's aesthetic . Classic female urban and vaudeville blues singers were popular in the 1920s, among them "the big three"--Gertrude "Ma" Rainey, Bessie Smith, and Lucille Bogan--and Victoria Spivey . Mamie Smith, more a vaudeville performer than a blues artist, was the first African American to record a blues song in 1920; her second record, "Crazy Blues", sold 75,000 copies in its first month . Ma Rainey, the "Mother of Blues", and Bessie Smith each "(sang) around center tones, perhaps in order to project her voice more easily to the back of a room". Smith would "sing a song in an unusual key, and her artistry in bending and stretching notes with her beautiful, powerful contralto to accommodate her own interpretation was unsurpassed". </P> <P> In 1920 the vaudeville singer Lucille Hegamin became the second black woman to record blues when she recorded "The Jazz Me Blues". These recordings were typically labeled "race records" to distinguish them from records sold to white audiences . Nonetheless, the recordings of some of the classic female blues singers were purchased by white buyers as well . These blueswomen's contributions to the genre included "increased improvisation on melodic lines, unusual phrasing which altered the emphasis and impact of the lyrics, and vocal dramatics using shouts, groans, moans, and wails . The blues women thus effected changes in other types of popular singing that had spin - offs in jazz, Broadway musicals, torch songs of the 1930s and 1940s, gospel, rhythm and blues, and eventually rock and roll ." </P> <P> Urban male performers included popular black musicians of the era, such as Tampa Red, Big Bill Broonzy and Leroy Carr . An important label of this era was the Chicago - based Bluebird Records . Before World War II, Tampa Red was sometimes referred to as "the Guitar Wizard". Carr accompanied himself on the piano with Scrapper Blackwell on guitar, a format that continued well into the 1950s with artists such as Charles Brown and even Nat "King" Cole . </P> <P> Boogie - woogie was another important style of 1930s and early 1940s urban blues . While the style is often associated with solo piano, boogie - woogie was also used to accompany singers and, as a solo part, in bands and small combos . Boogie - Woogie style was characterized by a regular bass figure, an ostinato or riff and shifts of level in the left hand, elaborating each chord and trills and decorations in the right hand . Boogie - woogie was pioneered by the Chicago - based Jimmy Yancey and the Boogie - Woogie Trio (Albert Ammons, Pete Johnson and Meade Lux Lewis). Chicago boogie - woogie performers included Clarence "Pine Top" Smith and Earl Hines, who "linked the propulsive left - hand rhythms of the ragtime pianists with melodic figures similar to those of Armstrong's trumpet in the right hand". The smooth Louisiana style of Professor Longhair and, more recently, Dr. John blends classic rhythm and blues with blues styles . </P>

Who made the most money from the recordings of old blues artists