Blues Transformations in the Music of Cream
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explanation of blues harmony views it in terms of scales; this is, I believe, misleading when discussing accompanied blues songs, since it undermines the strong harmonic basis of the instruments usually employed (guitar or piano). A melodic approach based on relationships around the chord tones as boundary pillars seems truer to the musical structure of such songs—particularly the melodic-harmonic dichotomy in Johnson's guitar technique—and regarding the harmonic tertian spans (between root and third, third and fifth, and fifth and seventh) as continuous tonal fields for melodic inflection obviates the need to tie melodic interpretation down to any specific notational representation or for arguments about the veracity of notating the third scale degree as systematically flatted or sharpened. The standard blues figure given in example 3.3 above is the most fixed version of this melodic traversing of harmonic spans, while the constant glissandi and moans in Robert Johnson's vocals represent perhaps the least fixed version. Future discussions of blues and rock music need to resolve or at least consider the harmonic versus melodic explanation for musical events. Second, central to Cream's transformations of blues songs is the creation of fixed signature riffs out of accompanimental motives and the concomitant evening out of rhythms and forms into consistent and continuous meters. The riffs, essential features of rock songs like Cream's "Crossroads," are seemingly transferred from a melodic to a harmonic basis—a process already evident in many Chicago electric blues songs. Thus, rather than figures embedded in an existing harmonic context, they begin to define that context, and, in some Cream songs, but to an ever greater extent in the music of Led Zeppelin and later bands, the riffs themselves become virtually the entire basis for the songs. In these cases, the pronounced metric settings of these riffs, which emphasize built-in syncopations invariably occurring within expanded upbeats to the following downbeat, are an integral aspect of the structure of the music. A thorough study and cataloging of the different aspects of the transformations of these riffs from blues to rock songs would be extremely useful for stylistic definition. Third, discussions of rhythm in rock music in relation to riffs, forms, and other levels of durations and proportions are often hampered by a confusion between rhythm and meter and how these arise from the grouping structures of harmonies, melodies, bass notes, phrasing, and other musical features. In regard to country blues, the problem is compounded by a confusion of perspective: is it more useful to regard, for instance, Robert Johnson's songs as beginning from a regular metrical basis, as many writers do, with the surface described as "irregular"? Or is an irregular (or, better, not necessarily regular) rhythmic approach more appropriate, with any regular surface meter regarded as a compositional and performance by-product of the grouping structures? Johnson's varied style and oeuvre suggests that not only may either approach be relevant for different songs, as in "From Four till Late" (regular, metric starting point) and "Hellhound on My Trail" (irregular, rhythmic starting point), but that both may be relevant even within the same song, as in "Cross Road Blues," if an adequate discussion of Johnson's complex assimilation of his musical heritage is to be achieved. Cream's regularizing approach strongly suggests that consistent meter is a primary structural determinant in their versions, but their awareness of the distinctions between rhythmic and metric patterns is clear in their