We're now officially back to a prelude and fugue from the cycle for which there is an online video performance, in this case by Asya Selyutina (as before). So you can follow along if you have the score as we look through this entry in Koshkin's cycle.
E major and E minor are arguably the most guitaristic keys in which a guitarist or non-guitarist can possibly compose. It's a key that is both forgiving and unforgiving. It's forgiving in the sense that there are a lot of things you can write and play that are idiomatic and rest easily on the instrument but it's an unforgiving key in the sense that whatever you bring to this key stands up against the entire history of the instrument in a way that a prelude and fugue in F sharp major never has to because very, very few guitarists are writing preludes and fugues in F sharp major.
I think Koshkin acquits himself well with this prelude and fugue and it's suitably emblematic to his approach to composing generally and for this cycle. Despite the key signature being E minor this is a prelude and fugue in drop D tuning
Prelude (start of video)
This is a languid and dark prelude. It opens with a short half measure gesture in common time, a widely spaced low range tonic triad with a melody rising up by arpeggiated eighth notes to an E minor ninth chord with an omitted fifth that is tacitly taken as having a fermata. This gesture is the introductory gesture and it eventually gets its own thematic expansion later in the prelude but the dominating idea is a slow and descending melodic line in the bass strings that is accompanied by a steady stream of sixteenth note figuration on the treble strings. Measures 2 and 3 are the bass melody gesture that establishes what we can think of as the first identifiably thematic/melodic material. This is followed by the sequential development of an idea in the bass strings that can be read as quarter note, dotted quarter note, eighth note and quarter note with different intervallic values and movements depending on context, which prevails from measures 6-9 (and 11-14).
A good rule of thumb I'd suggest for this prelude is that while you want to pay attention to the sixteenths as accompaniment throughout never think of them as the melodic content of this prelude. For that focus attention on all the notes that are longer than sixteenth note values.
The opening motto returns at measure 9 and gets a brief sequential expansion in measure 1
0. This leads to a new episode of the quarter, dotted quarter, eighth and quarter gesture with more sequential development. This passage ranges from measure 11 to the first half of measure 14.
In the second half of measure 14 through measure 15 we get another sequential presentation of the opening motto. This time the harmonies are not a static presentation of the tonic. An E minor triad sifts its way toward a first inversion A major chord and then a G major seventh chord with the F sharp at the bottom that, arguably, is an E minor ninth chord with an omitted tonic that doesn't formally appear until measure 16 with the return of the descending melodic gesture we've already identified as Theme 1 (as distinct from motto) material. If we think of the motto and the bass strings melody as being two distinct sections this prelude can be thought of as having a strophic form (a, a', a'', etc.) in which each episode is announced and offset by a presentation and/or sequential development of the motto followed by a bass strings melodic episode with sixteenth note figuration providing accompaniment in the treble strings.
Eventually the languid bass strings melody becomes less and less dominant as the prelude moves along and the motto takes on stronger and stronger thematic significance until it is finally the dominant thematic material.
This prelude, short though it is, is saturated with Phrygian and locrian elements and when it is minor it tends to be natural minor rather than a harmonic or melodic minor prelude. Even the penultimate harmony of this prelude, an E flat ninth chord without a fifth) "could" be construed as a leading tone that proceeds to the tonic of E minor but the melodic activity DESCENDS to E rather than rises to E natural as would be expected in a more parochial Western ideal of voice-leading.
The mood of the prelude is somber, even desolate, like something from a late period Shostakovich string quartet, if not quite as insistently despairing or dissonant.
Fugue (starts at 2:24)
As with the prelude, so with the fugue, we have a subject that is best described as E natural minor with a D natural and no leading tone. This subject is a short and punchy three-measure subject that, personally, I felt could have been a four-measure subject. It's not, and it works, but it feels like it could have been slightly longer.
Now what's interesting about this subject and exposition is that Koshkin could have introduced an answer at the dominant but instead he introduces an answer at the subdominant. Traditionally in Western contrapuntal practice the reason you answer at the subdominant is because your subject starts on the dominant scale degree and providing even a tonal answer at the dominant would destabilize your key regions too quickly (unless you're Anton Reicha and don't care about that in his 36 Fugues). In this case an answer at the dominant (i.e. having an A natural or even an A sharp that rises up to B before falling a fourth, as would be prescribed in the linear movement of the subject) drops the subject down to the subtonic degree of the minor mode. In other words, at a practical level, the dominant answer doesn't introduce enough pitches from the tonic chord to stabilize the key regions of the answers enough whereas a transposed modal answer at the subdominant DOES accomplish this, which is why Koshkin opted to answer at the subdominant (see measures 36-38). After a short transition the third voice enters at measure 40, giving us a clear-cut descending order of voices entering as soprano, alto and tenor/bass in this exposition.
The subject is agitated and gloomy, in the natural minor mode but with a brief chromatic turn into parallel major that presages some mutations that will appear later in the fugue. There are no countersubjects.
The first middle entry appears very early in this fugue (2:46) in D minor (measure 44). The next middle entry is in A minor at measure 45. Now at measure 53 we're firmly back in E minor with an episode full of stretto where the opening kernel of the subject is presented in successive stretto a beat apart. This builds up steadily through to measure 60 where we have a preliminary climax or false recapitulation in which the subject appears in E minor but modified so as to fit within the confines of the scordatura of the instrument. Koshkin signals that this is not, in fact, the climax of the fugue at about 3:25 (measure 63) by abruptly dropping down to piano and into the key of B flat, a tritone away from the tonic, as tonally far removed from "home" as we can possibly be in any kind of tonal traditions.
From 66 onward Koshkin feints at statements of the subject in F major but these sequential gestures never complete the subject and keep shifting downwards, so to speak, until we get to the next middle entry in D major (measure 71-73). At this point we can hear how the subject lends itself to modal mutation into parallel major by way of transposition and recontextualized harmony. As August Halm put it, a fugue subject needs to sound good subjected to mutation into parallel minor or major, it needs a melodic profile that can be subjected to any and every kind of modal mutation while still in some way being recognizable, and for all that sound pleasing, too. Koshkin hear demonstrates that his fugue subject sounds very pleasing in minor and major forms.
And, no surprise, he completes his middle entry in D major by going straight into an episode where he modally mutates back into D minor to re-establish the minor-key mood of the fugue overall at the end of measure 74. He sequentially extends the last measure of his subject toward a recapitulation of the subject in the tonic key. He hammers away at upper pedal tones on the topmost open strings but when the subject returns in full force it's presented in tenths and chromatically altered. The effect, which you can hear starting at 4:10, is loud and explosive. This is a quintessentially explosive Koshkin climax and it sounds boisterous and fun.
Now at this point, arguably, this spectacular, boisterous climax is great for a sonata but it is not necessarily a really polyphonic climax. There are two ways of responding to this observation. One is to say, yes, it's not exactly polyphonic at this point and perhaps a guitarist composer could or "should" choose to compose polyphony where the identifiable independence of the contrapuntal strands should be more perceivable and present. There's room for that conviction as ideas about counterpoint for guitar go. But there's a second response, which is to observe how very few cycles of fugues we have. Even in Bach's works, when he builds toward a climactic passage, he cuts loose and thickens his textures and expands his materials. He even modifies subjects and countersubjects as the interests of this or that musical work provide. I enjoy this piece so I am giving it a pass even if the contrapuntist in me could imagine ways in which fully invertible counterpoint might be provided for a subject like this. Not everybody has to think or feel the same way about this stuff.
By 4:19 (measure 91) we hit what could be the half cadence preparation (dominant pedal tone of D natural) for a jump into relative major. However, because of the persistence of the D natural as a MODAL minor subject we know that this pedal point on the subtonic is really setting up a winding down push for a cadence in E. In modal contexts there is no leading tone but the subtonic harmony frequently still plays a dominant or quasi-dominant role that leads back to the tonic rather than necessarily always setting up a relative major. This would be easier to site in any number of songs by, say, David Bowie than in Baroque counterpoint but seeing as we're in the 21st rather than the 18th or 19th century it's worth noting that in modal contrapuntal thinking we don't have a "leading tone" so the "rules" (whatever those may be) for tonal resolutions in modal ways of thinking aren't the same as textbook approaches to polyphony.
The fugue winds down steadily and relentless to measure 99 (4:39ish), where we hear the initial motto of the subject in augmentation and presented in a canon of call and response between bass strings and trebles. The last time the trebles take up the motto they sequence it down to another point of repose (4:53, first half of measure 105) before winding up for the final phrase in which the motto of the fugue resolves into a bright E major chord that bursts out of the treble strings and ends the fugue.