Sketch: Two-Voice Fugue for Guitar
Here's the sketch pad page wherein I composed the subject and its stretto possibilities.
Taking the tenor voice as the prime, you can see that the alto makes a stretto at a half-note of delay with the tenor, and the soprano - written here at the same pitch level as the alto - makes a stretto with the tenor at a measure and a half of delay. Not written out is the additional possibility of a third stretto at two and a half measures of delay. So, a two-voice fugue could be written with this subject with the strategic plan of ever closer stretti.
Finally, between the tenor and bass there is a two-voice hyper-stretto in which the prime and its augmentation start simultaneously. This is seriously cool, and I went ahead and wrote out the most obvious contrapuntal solution for its conclusion, as you can see.
What's unusual about these stretto possibilities is that the following voice always comes in on the weak beat (The final time signature is going to be 2/2). This produces a surprising out-of-sync effect that is very nice.
As for the subject itself, the intervallic leaps in the head are very interesting due to the minor mode and all the DINOs - Dissonances In Name Only - involved: After the initial minor third you get a diminished fourth (Which equals a major third), and then a diminished seventh (Which equals a major sixth). Obviously, this sequence of DINOs is also reflected in the closest stretto above, which makes that combination work (And only in the minor mode).
Looking closer at that stretto between the tenor and alto voices, the head intervals are; a major sixth, a diminished eleventh, and an augmented second which becomes a major third on the final eighth note of the second measure. this is a very gnarly sounding intervallic succession. In the third measure of that stretto the combination yields a minor tenth which becomes a perfect eleventh, and then a major tenth on the final eighth of that beat, so there is a tiny suspension chain there (Which is how that dotted-quarter/eighth rhythm came to be when I composed the subject).
The written-out trill figure creates an alternating minor tenth/major ninth succession with a perfect eleventh above the final sixteenth. So the final quarter note then, moves into a diminished eleventh/diminished twelfth/diminished eleventh alternation. As you can see then, this would never work in the major mode because parallel perfect fourths would result.
Note here that this subject lends itself perfectly to melodic inversion, which would make the head sol, me, le, ti (And yes, I'm aware that the hyper-stretto could then be three voices if the inversion was added to the mix).
With all of these possibilities, the resulting fugue could be positively epic. It could also take a year or more of work before the final perfect form materializes.
When faced with so many possibilities it is easy to become overwhelmed. The solution to this is to write out the simplest possible sketch first to see - and hear - how the most essential elements work together. This is also the best way to work out the countersubject possibilities.
The Create AAC option is still broken in the latest version of iTunes, so I'm going to have to resort to posting a General MIDI file. If you have the RealFont 2.1 GM soundfont set, you'll hear it with the Nylon Guitar 1 soundfont I use. Otherwise, you'll get whatever nylon string guitar sound you have set as your default.
Guitar Fugue Sketch
As you can see, I decided on D minor and a drop-D tuning for the piece, but I'm not at all positive that this will be the final key yet. At this point, Im just concerned with keeping the melodic peak as low as possible.
Also, I'm using a real answer versus a tonal answer, as I wanted to keep the uber-cool intervallic succession of the head intact: me is tonally answered by ti in minor, which didn't sound right to me at all. This necessitated a one measure link, which I went on to use subsequently to join all succeeding statements. Sure, I have some episodic material in mind, but in this first sketch, that isn't really needed as the primary goal was to start sorting out the key plan and working out the countersubject material.
I'm using straight quarter notes under the head here, but those could end up dotted quarters alternating with eighths in later versions. The countersubject/counter-answers are also just the most obvious solutions at this point.
For the statement beginning at measure nine I decided I wanted to hear how the relative major would sound. This results in a leapt-into major second above the dotted quarter in ten, but I actually love that result. I also had to change the final quarter note of the countersubject to sol from the potential mi to avoid parallel perfect elevenths, which sound particularly gauche to me in two voices.
This top stave statement in C major makes this like a counter-exposition in the relative, except that the thematic statements are a twelfth apart here instead of a fifth: I'm working my way up on the melodic peaks: The previous high was F, and here I'm up to A.
At seventeen we're back to the tonic key, and I'm using a descending chromatic tetrachord in the countersubject now. This is a cool thing to save for near the end. The final statement before the stretto also uses this device, and note that no linking measure is required with this arrangement.
Finally, the closest stretto is presented as the conclusion, but not the hyper-stretto, which will have to await a future version.
So, this is how you begin an epic fugue; by working out the combinations of the subject, and then composing a very basic initial version. In future iterations I'll add episodic material, the additional stretto possibilities, perhaps some of the melodic inversions, and the hyper-stretto as a conclusion.
Like I said, it could be epic.