Chords of different tone quality used alternately.
1. The most usual practice is to employ chords on different groups of instruments alternately. In dealing with chords in different registers care should be taken that the progression of parts, though broken in passing from one group to another, remains as regular as if there were no leap from octave to octave; this applies specially to chromatic passages in order to avoid false relation.
Examples:
[No. 239.] Ivan the Terrible, Act II 29.
[No. 240]-[241]. The Tsar's Bride 123, before 124.
* [No. 242]-[243]. """ 178, 179.
* Note. The rules regulating progression of parts may sometimes be ignored, when extreme contrast of timbre between two adjacent chords is intended.
Examples:
* Shéhérazade, 8th bar from the beginning, (the chromatic progression at the 12th bar is undertaken by the same instruments, the 2nd cl. is therefore placed above the first in the opening)—cf. [Ex. 109].
* The Christmas Night, opening (cf. [Ex. 106]).
2. Another excellent method consists in transferring the same chord or its inversion from one orchestral group to another. This operation demands perfect balance in progression of parts as well as register. The first group strikes a chord of short value, the other group takes possession of it simultaneously in the same position and distribution, either in the same octave or in another. The dynamic gradations of tone need not necessarily be the same in both groups.
Examples:
Ivan the Terrible, commencement of the overture (cf. [Ex. 85]).
[No. 244.] Snegourotchka 140.