Harmonic basis.
Melodic design comprising notes foreign to the harmony, passing or grace notes, embellishments etc., does not permit that a florid outline should proceed at the same time with another one, reduced to essential and fundamental notes:
[[Listen]]
If, in the above example, the upper part is transposed an octave lower, the discordant effect produced by the contact of appoggiaturas and fundamental notes will be diminished; the quicker the passage is played the less harsh the effect will be, and vice versa. But it would be ill-advised to lay down any hard and fast rule as to the permissible length of these notes. There is no doubt that the harmonic notes, the thirds of the fundamental one (E) are more prominent from their proximity with the notes extraneous to the harmony. If the number of parts is increased (for instance, if the melodic figure is in thirds, sixths etc.), the question becomes still more complicated, since, to the original harmonic scheme, chords with different root bases are added, producing false relation.
Nevertheless, for the solution of such problems, orchestration provides an element of the greatest importance: difference of timbres. The greater the dissimilarity in timbre between the harmonic basis on the one hand and the melodic design on the other, the less discordant the notes extraneous to the harmony will sound. The best example of this is to be found between the human voice and the orchestra, next comes the difference of timbres between the groups of strings, wood-wind, plucked strings and percussion instruments. Less important differences occur between wood-wind and brass; in these two groups, therefore, the harmonic basis generally remains an octave removed from the melodic design, and should be of inferior dynamic power.
Examples of harmonic basis in chords:
[No. 264.] Pan Voyevoda, Introduction.
Legend of Kitesh, Introduction (cf. also [Ex. 125] and [140]).
* Mlada, Act III 10.
The harmonic basis may be ornamental in character, in which case it should move independently of the concurrent melodic design.
Examples:
* [No. 265]-[266]. Tsar Saltan 103-104, 128, 149, 162-165 (cf. below).
Chords the most widely opposed in character may be used on a simple, stationary harmonic basis, a basis, founded, for example, on the chord of the tonic or diminished seventh.
Examples:
[No. 267.] Legend of Kitesh 326-328—Wood-wind and harps on a string basis.
[No. 268]-[269]. Kashtcheï the Immortal 33, 43.
[No. 270.] Mlada, Act II, before 17, 18], 20.
[No. 271.] The Golden Cockerel 125—Chords of the diminished seventh, on arpeggio basis (augmented fifth).
The effect of alternating harmony produced between two melodic figures, e.g. one transmitting a note, held in abeyance, to the other, or the simultaneous progression of a figure in augmentation and diminution etc. becomes comprehensible and pleasant to the ear when the fundamental sustained harmony is different.
Examples:
Legend of Kitesh 34, 36, 297 (cf. [Ex. 34] and [231]).
[No. 272]-[274]. Tsar Saltan 104, 162-165 (cf. also 147-148).
* Russian Easter Fête, before V.
The whole question as to what is allowed and what forbidden in the employment of notes extraneous to the harmony is one of the most difficult in the whole range of composition; the permissible length of such notes is in no way established. In absence of artistic feeling, the composer who relies entirely on the difference between two timbres will often find himself using the most painful discords. Innovations in this direction in the latest post-Wagnerian music are often very questionable; they depress the ear and deaden the musical senses, leading to the unnatural conclusion that what is good, taken separately, must necessarily be good in combination.