I am hoping someone intimately familiar with Tchaikovsky's orchestral
habits may be able to answer this question: Did he sometimes have the
cellos and basses alternating between playing in unison and playing in
octaves? (I know that he did all sorts of curious things in terms of cross
voicings, having the basses cross above the cellos, for example, etc.) An
arranger told me this was a "trick" he picked up from Tchaikovsky, yet I
myself cannot think of any examples off hand.-
William H. Rosar
Editor
The Journal of Film Music
www.ifms-jfm.org
One reason why a composer may alternate unisons and octaves is to avoid
notes which fall below the range of one or the other instrument (or
section). In the last movement of Symphony No. 4, the cellos and basses
begin the main subject in unison, with the basses in a high register.
Mid-way through the third measure, the cellos reach their low C and jump
up one octave, so that the two sections finish the phrase in octaves.
Now look at the first fff statement of the main subject in the third
movement of Symphony No. 6 (m. 229). The cellos and basses play in octaves
for most of the first three measures, but in the fourth measure the basses
reach their lowest note and play the Eb and D an octave higher, in unison
with the cellos.
If you look at the parts for third trombone and tuba, or first and
second bassoon, you will find many examples of the same device.
Nicolas Krusek
In addition to overcoming instrumental range limitations as Nicolas
Krusek cogently explains, I suspect that there are other reasons as well
related to part writing, especially in homophonic chordal passages, such
as those involving parallel movement or similar movement, in this
instance, to make the bass line stronger and more dynamic by introducing
contrary motion where there might be none. For example, instead of a bass
line in a given chord progression ascending in whole steps, by alternating
unisons and octaves on the bottom, it breaks up the stepwise movement
which, in a bass line, is not necessarily desirable, unlike the
tradition in melodic writing, where stepwise movement is typically
preferable.
If one looks at the beginning of the slow mvt. to the 5th symphony,
Tchaikovsky cross voices the cellos and basses in such a way that the
basses are often rising or falling an octave, even though the actual bass
line in those instances is moving stepwise. A similar procedure can be
observed in the last mvt. of the 6th with the opening progression of
parallel chords, in which the string parts actually zigzag rather than
move in parallel motion downwards, even though the whole texture is moving
in parallel motion. There is an old 78 rpm recording in which the
strings glide (portamento) between pitches and one can clearly discern
their zigzag movement in this passage (I thought it was the old Mengelberg
recording, but just now checking, it is not). It would be interesting to
determine if this was an innovation of Tchaikovsky's, or something that he
learned in studying orchestration (perhaps from the French).-
William H. Rosar
Mr. Rosar refers to an unusual device of orchestration in the opening
measures of the Fifth Symphony's slow movement. The double basses and the
cellos alternate in providing the bassline, contrary to the usual rules of
part-writing. This is an example of a procedure that Tchaikovsky used in
various works, where a line in a texture, or even an entire texture, is
alternately played by two groups of performers. An illustration of the
latter is in the Fourth Symphony's scherzo (starting in measure 365),
where strings (playing pizzicato) and wind instruments (woodwinds and
horns) switch roles in rapid and regular succession (one beat per group of
instruments).
Mr. Rosar could well be correct in suggesting that French music may
have provided Tchaikovsky with a starting-point: Berlioz is a possible
precursor—see the March to the Scaffold from the Fantastic Symphony
(m. 82 onwards). However, it should be emphasised that the Romantic-period
usage of this method is an apparently unwitting re-establishment of a
device from the medieval period: the so-called 'hocket' (to which the word
'hiccup' is etymologically related), which is described in, e.g., The
New Grove Dictionary of Music and Musicians. Berlioz and Tchaikovsky,
like other Romantics, are extremely unlikely to have been aware of the
provenance of this procedure in the Middle Ages, whose music had long been
the domain of scholars, rather than composers.
Henry Zajaczkowski
musicologist