This week we mark two extraordinary centenaries. Sir David Attenborough’s, of course, but only four days after the birth of the bona fide national treasure, Dmitri Shostakovich’s First Symphony also first saw the light of day – premiered in Leningrad on 12 May 1926. The 19-year-old’s composition was played by the Leningrad Philharmonic, conducted by Nicolai Malko.

The symphony’s four-movement structure is just about the only conventional feature it has. The teenage Shostakovich had imbibed all the lessons he could about what orchestral music should sound like and how it should behave, and was bold enough to subvert all those ideas and send them up. There is no forelock-tugging to earlier generations of Russian symphonists and orchestral pioneers; instead, Shostakovich’s First resounds with a self-confidence that’s both optimistic and deliciously sardonic.

From the distorted trumpet call that opens the work – a fanfare that thumbs its nose at your expectations of how a symphony should start; not an affirmative flourish, but a snakingly dissonant question mark – Shostakovich sets out on a first movement that’s like a circus: a cavalcade of characters who take the stage and exit, more often than not pursued by a cartoon bear, clown or bassoon. The momentum that Shostakovich generates from the way he juxtaposes ideas – cutting from one to the other as if the symphony were a reel of film – continues deliriously in the second movement. Here, a piano part is added to the orchestral texture, and that’s where one of the secrets of this music’s compositional energy is revealed. As a teenager, Shostakovich played the piano for Soviet silent cinema screenings, and in the symphony’s piano solos, he turns his work into a knockabout farce that Buster Keaton would be proud of.

The movement builds to a climax that is both terrifying – a sudden fanfare that consumes the whole orchestra – and bathetic, in the form of the solo piano’s chords, as if the pianist couldn’t keep up with the music’s pace.

There is no hint anywhere in this piece of the bombast and poster-paint ideology of Shostakovich’s later symphonies, but there is real feeling here, hinted at in that climax of the scherzo, as the cartoon suddenly shudders into real life. The slow movement that comes next is one of the most unironically passionate that Shostakovich ever wrote, as a solo oboe and solo cello inspire the whole orchestra to a melodic outpouring that feels more Shakespearean drama than circus hijinks.

The final movement somehow brings all of these worlds together, and the symphony ends in a torrent of irresistible energy, a culmination of pure sentiment as well as sheer excitement. This is, surely, the most creatively confident First Symphony by any teenager in musical history (and there is plenty of competition, from Mendelssohn to Knussen, from Rihm to Schubert). It announces a world of possibility in which musical conventions are gleefully turned upside down in a frenzy of modernist creativity that’s both funny and profound. It’s the sound of a unique symphonic avant garde that might have heralded an era of unfettered creative freedom for Shostakovich and generations of composers.

Instead, these are the sounds of what might have been, for Shostakovich and for Russia. In Shostakovich’s later symphonies, especially from the mid-1930s onwards, you hear the chilling of that freedom and the daily terror of living in Stalin’s Soviet Union. The confidence and joy in his own brilliance that you hear in every page of the First Symphony is a miracle that Shostakovich never quite repeated and which is still strikingly new, a century on.

This week, Tom has been listening to: Elgar’s Viola Concerto. Yes, seriously: in the viola player Timothy Ridout’s searingly expressive recording of Lionel Tertis’s version of Elgar’s Cello Concerto – an arrangement that Elgar approved and conducted with Tertis himself as the viola soloist – the soul of this music is somehow even more powerfully resonant than in the original, with the human range and exquisite vulnerability of the viola’s sound-world.