The primary determinants of musica l foml in tonal music were tonality and theme, withcontrast of tonalities being a generally stronger force than contrast of themes. The declinein tonality as an organizing force has often led to a greater reliance on thematic contrast;but in many pieces, themes, in the sense of melodies, pla ya small or nonex istent part. Themost obvious example is electronic music, where texture, register, dynami cs, and especial MIy timbre are usua ll y more important as shaping elements than themes are. Rhythmic ac-ti vity is another organiz in g factor

INSTRUMENTATION AND ORCHESTRATION

TEXTURE AS A FORM DETERMINANT

SECTIONAL VARIATIONS

NONTHEMATIC DELINEATORS OF MUSICAL FORM

SCALE FORMATIONS IN TWENTIETH-CENTURY MUSIC

MUSIC FROM OTHER CULTURES

CHOICE IN PERFORMANCE

INFLUENCES FROM FOLK MUSIC, JAZZ, AL'ID ROCK

FORM IN TWENTIETH-CENTURY MUSIC

SERIALIZED RHYTHM AND ISORHYTHM

TEMPO MODULATION AND POLYTEMPO

WRITTEN RHYTHM AND PERCEIVED RHYTHM

PANDIATONICISM

VOICE LEADING IN TWENTIETH-CENTURY MUSIC

INTRODUCTION 46 CONVENTIONAL TERTIAN SONORITIES 47 TERTIAN CHORDS WITH ADDED NOTES 49 TERTIAN CHORDS WITH SPLIT CHORD MEMBERS 52 OPEN-5TH CHORDS 54 QUARTAL AND QUINTAL CHORDS 55 SECUNDAL CHORDS 59 MIXED-INTERVAL CHORDS 62 WHOLE-TONE CHORDS 63 POLYCHORDS

OTHER POSSIBILITIES

MICROTONAL SCALES

CHROMATICISM AND MUSICAL FORM

THE TWILIGHT OF THE TONAL SYSTEM