|Op 87 - No. 9 - E major - Fugue|
Among the total of 72 fugues of Shostakovich and Bach, there are only two fugues in two voices, one from each composer. (Bach's two-voice fugue is Book 1, No. 10 in E-minor, likely a familiar piece of music to most listeners.) Like its Bachian counterpart, this fugue is an utter delight.
In fact, this fugue is literally like Bach's two-voiced fugue in a number of ways. Both present a clean, crisp two-part counterpoint that has the lightness and clarity and even a brevity of a two-part invention. The consistent rhythmic drive, predominantly in 16th notes, gives both fugues a quality of perpetual, unbroken motion. With two voices, it is almost automatic that both fugues would feature exactly one countersubject. And upon closer inspection, you will see that even the subjects seem related:
Notice in particular, the first measure, beats two and three: both feature 8th note "wedge" motives that are very close to inversions of one another.
Shostakovich continues the program of inversion by delighting us throughout the fugue with clear statements of both subject and countersubject in their inverted forms. It pleases with a deep sense of symmetry and completeness, as if Shostakovich left no stone unturned in a treatment of two voices with two primary melodic ideas.
It would seem that this mark of elegant symmetry extends beyond the particulars of Shostakovich's fugue to the overall fact of its mere existence as counterpart to Bach's fugue; they form a pair. In a completeness typical of Bach himself, the pair fit nicely together not only for their similarities, but also because they are complimentary: one is in E-minor, the other, E-major. It makes wonderful sense that there ought to be at least two, two-voiced fugues. And as, in this case, Shostakovich is so good at being like Bach, it almost feels like he came up with something that one might say was almost missing before. Certainly, now that we have heard it.