e professor of free counterpoint.
It remains to be noted that the human voice accompanied by
the orchestra is always heard independently as something
apart, something complete in itself. For this reason a
composer may never rely on the orchestra to fill up an empty
space or correct a fault in the handling of voices. All the
rules of harmony and counterpoint, down to the last detail,
must be applied to vocal writing, which is never dependent
upon orchestral accompaniment.

Trios, quartets etc.

All that has been said regarding the relationship of voices in duet
applies with equal force to the combination of three, four, five or
more voices. An _ensemble_ of several voices is seldom purely
polyphonic; as a rule, although some parts move polyphonically,
progression in thirds, sixths, tenths and thirteenths is used for the
remainder. Declamation for some voices on notes forming the harmony is
also possible. This variety of simultaneous movement of vocal parts
renders the comprehension of the total effect less difficult for the
ear, and sanctions the distribution of distinctive and suitable
figures or tone colouring to certain voices with other figures or
timbres which may be proceeding at the same time. The skilful
arrangement of pauses and re-entries facilitates the understanding of
the whole, and gives desirable prominence to detail.

_Examples:_

_Snegourotchka_ [[267]]--Trio, Finale to Act III.

_The Tsar's Bride_ [[116-118]]--Quartet in Act II.

" " " [[168-171]]--Sextet in Act III (cf. extract, Ex. 283).

_Servilia_ [[149-152]]--Quintet in Act III.

The movement of solo voices is seldom purely harmonic in character
with predominance given to the upper voices homophonically treated.
The blending of all the parts into an harmonic whole, without any
distinctive predominant feature in any one part (as in a chorale) is
employed for songs or _ensembles_ in traditional style, prayers,
hymns, etc. If this method is adopted for the quartet of voices,
Sopr./Alto/Ten./Bass, it will be noted that widely-spaced part writing
is the most natural and suitable form (especially in _forte_
passages), as the four voices can sing together in their proper
registers (low, middle and high), while, in close part writing they
may find themselves at a given moment in registers, which are entirely
foreign. But both methods should be employed, as, otherwise, it would
be impossible