Bimodality is the simultaneous use of two distinct pitch collections. It is more general than
bitonality Polytonality (also polyharmony) is the musical use of more than one key simultaneously. Bitonality is the use of only two different keys at the same time. Polyvalence or polyvalency is the use of more than one harmonic function, from the same key, a ...
since the "scales" involved need not be traditional scales; if diatonic collections are involved, their
pitch center
In music, the tonic is the first scale degree () of the diatonic scale (the first note of a scale) and the tonal center or final resolution tone that is commonly used in the final cadence in tonal (musical key-based) classical music, popul ...
s need not be the familiar major and minor-scale
tonics. One example is the opening (mm. 1–14) of
Béla Bartók
Béla Viktor János Bartók (; ; 25 March 1881 – 26 September 1945) was a Hungarian composer, pianist, and ethnomusicologist. He is considered one of the most important composers of the 20th century; he and Franz Liszt are regarded as H ...
's "Boating" from ''
Mikrokosmos'' (no. 125, vol. 5). Here, the right hand uses pitches of the
pentatonic scale
A pentatonic scale is a musical scale with five notes per octave, in contrast to the heptatonic scale, which has seven notes per octave (such as the major scale and minor scale).
Pentatonic scales were developed independently by many ancien ...
on E and the left hand uses those of the
diatonic hexachord on C, perhaps suggesting G dorian or G mixolydian.
Bartók also uses the white-key and black-key collections (diatonic scale and its pentatonic complement) in no.6 of the ''Eight Improvisations'', with the pentatonic as foreground, and in mm. 50–51 of the third movement of his Fourth Quartet, with the diatonic as foreground .
Paul Wilson argues against analyzing Bartók's "Diminished Fifth" (''Mikrokosmos'' vol. 4, no. 101) and "Harvest Song" (no. 33 of the Forty-Four Duos for two violins) as bitonal since in both "the larger
octatonic
An octatonic scale is any eight-Musical note, note musical scale. However, the term most often refers to the symmetric scale composed of alternating major second, whole and semitone, half steps, as shown at right. In classical theory (in contras ...
collection embraces and supports both supposed tonalities" . Here, the octatonic collection is partitioned into two four-note segments (4-10 or 0235) of the natural minor scales a tritone apart.
Sources
*
*{{wikicite, ref={{harvid, Wilson, 1992, reference=Wilson, Paul (1992). ''The Music of Béla Bartók''. New Haven and London: Yale University Press. {{ISBN, 0-300-05111-5.
Musical techniques