LXXXVI.

"In the case of Bartók and Stravinsky we find rather the phenomenon of extended tonality, which likewise already had its origins in the nineteenth century. In extended tonality a central, centripetal effect persists and is indeed so strong that even relatively complex harmonic structures cannot undermine it. Elementary harmonic functions still occur, but the forces active at the centre are often of a horizontal nature. Extended tonality may be manifest in numerous variants: from the simple addition of modal elements, parallel harmony, intermixture of major and minor, added notes etc., to polytonality with various simultaneous centres. For the rest, the actual concept of extended tonality is very closely related to our aural capacities. What perhaps sounds chaotic and ‘atonal’ to an untrained listener may be perfectly cohesive to the insider. What was considered polytonal in 1920 is today monotonal, if we are but able to relate all the parts to one centre."

© Ton de Leeuw
"Music of the Twentieth Century: A Study of Its Elements and Structure" (1991)
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