ANOTHER WAY OF GOING BEYOND THE TWELVE TONES PER OCTAVE
Let's examine two very-much-performed compositions--perhaps over-performed. Schubert's Unfinished Symphony in B Minor, and Tchaikovsky's Sleeping Beauty Waltz.
Presumably, these standard compositions by standard 19th-century composers, played by conventional orchestras with conventional instruments, ought to be "conservative" enough to meet the demands of the most reactionary music critics and music teachers and concert promoters and the most hidebound traditional conductors who would never touch a 20th-century piece with a 10-foot pole.
They are, then, part of the increasingly-shrinking repertory of the classics or what the average music student is brought up on and the kind of music that is used for background to something else or when records have to be played to fill in what would otherwise be uncomfortable silence.
Dead composers earn no royalties: they are public domain; the performers and conductors and the recording industry, &c., may mine them to exhaustion as Public Domain.
For the present purpose: Both these works contain passages which imply intervals smaller than the semitone, or which imply a possible distinction of pitch between such "enharmonic pairs" as C-sharp and D-flat, and even though this cannot be done on a keyboard instrument tuned in 12-tone equal temperament, it is now possible to have other tunings on keyboard instruments, to effect synthesizer or computer or automatically-played performances, and in this way more than 12 pitch-classes per octave become practical and affordable, where they were out of the question or prohibitively expensive hitherto.
Examination of the score of Schubert's Unfinished Symphony will show many changes from a C-sharp to a D-flat or other such pair of notations. It can't be pure ornament or musical "orthography" in this case even if it can be explained away on many other occasions (Beethoven going to sharps to avoid an embarrassing accumulation of double-flats if he went to the key of C-flat minor, for instance, so with a flurry of naturals he fled to B minor instead).
There is a passage in the second movement of the Schubert Unfinished which starts in F major. It gets into C-sharp minor, and then goes to D-flat major. There is~no real reason to make this change if it were just a matter of rules--it could have been notated as C-sharp major equally well and would have looked less confusing. But it goes to D-flat and back to C-sharp minor again. And a few orchestras including one I was in, played a different pitch for the D-flat and A-flat than they had just played for C-sharp and G-sharp. So these passages ought to be tried on new instruments or computers in the 19, 22, 31, and just tuning-systems.
In Tchaikovsky's Sleeping Beauty Waits are several places where in the normal performance in 12-tone equal temperament a written dissonant diminished sixth (that would be like G-sharp against F-flat) is played and heard as a consonant fifth. That spoils, or lets us down, or takes the "zip" out of the effect that, should be there. Again musical experimenters ought to try this waltz, using a dissonant interval in that place. We wonder: just how was Tchaikovsky's piano tuned at the time he was composing that piece? We will never know, of course. But could it have been meantone, or some compromise tuning? Remember, a Russian piano-tuner a century ago in some small town, with no electronic magic tuning-device!
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