At the turn of the 20th Century, a number of composers were beginning to explore
the sound world of bitonality, the use of more than one key simultaneously. Composers
like, Bartók, Stravinski and Ives all explored bitonality in their music.
Debussy's second book of Preludes explores the blending of keys - as does my own
set of 12 Preludes.
Some theorists
consider notation in two keys to be pointless, because the purpose of a key
is to suggest a root or tonic. With bitonality, there is no common tonic, and
so the keys become irrelevant. And yet surely the point of a key signature is
to also aid in the reading/performing of the music?!?
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| Prelude 2 |
In writing my own set of preludes I ran into a problem. The preludes explore
bitonality in the migration of keys through the circle of fifths, with each
hand moving in a different direction through the keys. So, the first prelude
has both hands in C, but the second prelude has the right hand in G while the
left hand is in F. For this piece, the "tonality" ends up being in
D with a flattened 7th - occasionally flattening the 6th, which gives the piece
a nice jazz feel.
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| Prelude 3 |
Prelude 3 had more difficulties. It was originally written with each hand playing
only in its key, but this created some very un-pianistic passages. So the piece
was re-written with a number of accidentals. Prelude 4 was even worse for the
pianist and so key signatures were scrapped entirely.
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| Prelude 4 |
The key signatures return for the fifth prelude with the keys of A-flat and
E. Yet, in the sixth prelude I opted to write it in the key of C-sharp (7 sharps),
then flatten or sharpen the necessary notes to create the keys of B and D-flat
(enharmonically). The seventh prelude is written in 6 sharps as F-sharp and
G-flat are the same key on the piano - so in many respects I had returned to
what the first prelude experienced, mono-tonality the seventh ends in the relative
minor whereas the first prelude ends in major.
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| Prelude 7 |
What I discovered in the process was sometimes key signatures are a hindrance
to the performance of a piece. Pretty much every pianist who has looked at the
preludes suggests they should be written without a key and just place accidentals
where necessary. However, I feel by putting in the key signatures I am encouraging
the pianist to "think" in multiple keys, which - if pianists ever
get to the point they are truly thinking that way, the music they will conceive
will be vastly different than what we experience today; they will discovered
a blending of the keys we don't understand.
This is rather like someone learning another language. The second language
is difficult to learn, the third not so much and from there learning another
language just gets easier as grasping linguistic concepts across multiple languages
gets easier with more languages to draw on.
When working with multiple keys, I found it important to understand the common
points. Even with keys as remote as A and D-flat (fourth prelude) there are
points where the two keys intersect. There intersections then become the focal
point for propelling the composition forward, although they may or may not end
up being the "tonic" or resolution notes.
Then it is important to look at the complex scale, the meta-scale of both keys
combined. What is the mode presented with the meta-scale? In the case of the
second prelude, D is the relative minor for F and the dominant for G, so an
easy key to migrate toward in terms of working with these two keys. I would
say playing meta-scale and listening to it again and again to gain a sense of
its migration might work, however, this tends to point toward the use of pre-conceived
tonal leanings and not necessarily allow for something new. This is the process
I used with the first few preludes (up through prelude 6) and why I feel these
early preludes are not as strong as the later ones - where I took a more analytical
approach to determining the key note for the piece.
Some of the preludes move harmonically similar to mono-tonal piece in that
chord structures can be analysed showing a IV, V, I progression. However, other
preludes tend to move harmonically linearly, moving the harmonies up or down
along the scale. Still other preludes are grounded in a tonal center, shifting
the tonal centre at times, to create harmonic movement, but not in a typical
cadence type manner.
As tonality moves forward, I think there will be more exploration of this sort
of bitonality and the resulting harmonies. Perhaps we will not need to express
the music in terms of a written key (as we know it today) - but bitonality can
create vastly definitely different harmonic movement from standard tonal progressions
- and thus opens a whole new world to possibilities.
Notes:
While the project of writing these preludes helped me discovered some interesting
aspects of bitonality, and perhaps a better understanding as to what happen
harmonically when two keys merge. However, looking back on these pieces (after
more than a year) I realise they aren't as successful at achieving a true sense
of bi-tonal writing. Part of the problem is the way I approached determining
the two keys. I think, if I had a method of determining keys that wouldn't eventually
be the same key enharmonically the resulting pieces (at least the first and
seventh) would have been bi-tonal.
It is interesting to me that Prelude 4 and Prelude 10 are in the same keys
(with the hands reversed) and yet, Prelude 4 centers around D while Prelude
10 centers around B (it was by choice they are different).