Mediant Key Schemes and Deep-Level Chromaticism in Three Brahms Chamber Works

Carissa Reddick, University of Connecticut

A hallmark of Brahms's style, and of nineteenth-century music in general, is movement between third-related keys. One type of mediant relationship, minor tonic to its relative major, is a convention of sonata-form expositions in minor mode. In several of his sonata-form movements, however, Brahms exploits mediant relationships that depart from "normal" sonata key schemes. This paper examines the ramifications of these unusual key schemes on linear structure, and the resultant structure's interaction with the sonata form principle, in the first movements of three of the composer's chamber works: the Piano Trio opus 8 (in its revised version of 1889), the Piano Quintet opus 34 (1862), and the String Quintet opus 88 (1882).

All three of these movements exhibit an uninterrupted linear structure with a Kopfton on 5. The key schemes of these movements by Brahms, however, prohibit the subordinate theme from prolonging 5 at the deep middleground level. Therefore, the subordinate theme group in each of the movements prolongs an upper neighbor to the Kopfton. Because of the chromatic nature of Brahms's style, this upper neighbor is prolonged in both of its modal variants: a half-step above 5 (♭6) and a whole step above 5 (♮6). The prolongation of both variants injects the deep middleground structure with chromaticism that is not present in an uninterrupted sonata-form movement with a standard key scheme. This paper draws on previous work, especially Roger Graybill's exploration of Brahms's three-key expositions, Boyd Pomeroy's ideas on formal fusion, and Peter H. Smith's theories of form and "dimensional noncongruence."