The chamber symphony, which
constitutes a whole in and for itself and has no
following music in view, reaches its goal only through a full sounding,
brilliant, and fiery style. The allegros
of the best chamber symphonies contain great and bold ideas, free handling of
composition, seeming disorder in the melody and harmony, strongly marked
rhythms of different kinds, powerful bass melodies and unisons, concerting
middle voices, free imitations, often a theme that is handled in the manner of
a fugue, sudden transitions and digressions from one key to another, which are
all the more startling the weaker the connection is [between them], [and]
strong shadings of the forte and piano, and chiefly of the crescendo, which, if
it is employed at the same time as a rising and increasingly expressive melody,
can be of the greatest effect. Added to
this comes the art of connecting all the voices in and with one another so that
their sounding at the same time allows only one single melody to be heard,
which requires no accompaniment, but to which each voice contributes its part.
Sonata form as found in the
18th-century symphony should be understood as encompassing a wide
range of variants; indeed it is less a form than a flexible collection of
characteristic procedures and techniques.
These include contrast and directional modulation between tonic and
dominant or other related key areas; differentiation and functional
specialization of thematic material; slowing of harmonic rhythm to articulate
and stabilize thematic areas; development involving modulation and changes in
material; recapitulation; and orchestration and textural differentiation that
selectively enhance these procedures.