Note: Before looking at my example, you can read my old research from Part 1 of the course regarding baroque inventions, as well as the posts about the flute (piccolo) and vibraphone, which I use here. You can also take a look at my listening log post about Bach’s fugues and inventions I listened to.
Project 12 is about composing two contrasting two-part inventions of between 8 and 20 bars, using techniques of imitation, inversion, augmentation and diminution. I decided to write the first invention in the baroque style. Here is the full score:
Below is the audio:
Analysis and reflection
Initially, I wrote the theme for the flute and vibraphone. However, while I liked the musical content, I wasn’t satisfied by the way the timbre of the two instruments interacted. Aiming for a higher register, I changed the flute into piccolo. I think it works much better – the sound is a bit more unique and the instruments blend more efficiently. Also, Sibelius doesn’t play the registers of the vibraphone evenly. I tried to change this, but couldn’t really achieve how I wanted it to sound. In performance though, this shouldn’t be a problem.
For the analysis, I will look at my invention through the musical rhetoric, which influenced my compositional process. (Take a look at the blog post in the note above at the beginning of the post.) The two-part inventions are monothematic, and with the limit of 20 bars, the forms are much shorter. The piece starts in D major with the exordium (bars 1-2) that introduces the main motif of the piece:
As well as the continual or permanent countersubject – what occurs in nine of Bach’s invention, such as Eb major, f minor, g minor and other. Here is the permanent countersubject:
After the imitation of the main motif in vibraphone, exordium then expands into narratio (bars 3-6), which begins with a sequence (bars 3-4). The sequence uses the slightly varied rhythm of the main motifs in the vibraphone, while this is a bit more changed in the piccolo – for example, the dotted crochet appears. The minor third jump is also inverted from down to up, but more than that, the rhythm appears in a backward inversion, so that the motif
It’s also interesting how the two voices interact – a kind of imitation with augmentation, so that
from the vibraphone in the piccolo becomes:
Harmonically, the sequence is based on the descending third – harmonically: I – V, vi – V/vi, using the secondary dominant to modulate to D major’s dominant key – A major. This is the usual modulation for the major inventions. After the modulation, the key is confirmed by the cadential ending (bars 5-6). Note that there is a dissonance – minor 7th G# – F#, however, I don’t think it’s that audible and while not really properly resolved, it goes away quite quickly. It would clash a lot more if it were the interval inversion – major 2nd that appeared instead.
In a longer invention, the following parts would be propositio, and afterwards the argumentatio. Because of the short form, I kind of blended the two (bars 7-14). This section starts with propositio simplex (bars 7-8), where the main motif with the continual countersubject is repeated with the voices in inversion. In the first appearance, the main motif is in the piccolo section, and then imitated with vibraphone. Now, it is the other way around – the vibraphone starts the main motif, which is imitated by the piccolo.
Next is the propositio complex (bars 9-11). It based on a sequence, where A# suddenly appears and the modulation leads to D major’s relative B minor – again, a key that usually turns up in Bach’s inventions. The sequence is formed around
which is based on the earlier rhythmic figure from the sequence and cadence of the narration. It is first played by piccolo and then in vibraphone, using a sequential imitation, so that the tones are raised from vii to I.
Then, the main motif appears again in argumentatio (bars 11-14), however in E minor. It then modulates to G major, and the material is quite free (bars 12-13), with some imitation again. It ends with cadential ending (bar 14) similar to bar 5, only now leading back to D major.
Finally, the invention ends with peroratio (bars 15-19). It begins with the repetition of the main motif and countersubject, first in the vibraphone with imitation in the flute. In the coda-like ending cadence, there is the myxolidian turnaround which is the sudden modulation to subdominant region which appears with the C natural in bar 15 – often seen in baroque music. This is once again followed by the imitation.
Generally, I am quite happy with the piece, especially in terms of following the baroque style – the important elements of its melody, harmony and counterpoint. I think I have also demonstrated good use of the techniques which the brief asked for, although here it’s mostly imitation, while the inversion is based more on backward inversion of the rhythm and switching between the voices, and there’s some traces of augmentation. Still, I believe I utilized these effectively. Leaving the baroque behind, the next invention will explore augmentation and diminution more, as well as the inversion in the melodic sense, while stylistically switching to the modern era. Take a look here.