Of all those big post-war avant-garde names who used to dominate the landscape - Boulez, Stockhausen, Berio, Cage, Nono, Ligeti - the one whose music I always got the greatest kick out of was the Greek Iannis Xenakis (1922-2001). You would often read about the complex mathematics behind his pieces (works based on set theory, statistical mechanics, Brownian motion, etc) and then, when you actually listened to them, almost invariably find this music sounded far more like a force of nature - and was exhilarating to hear.
I have an especial liking for those pieces where Xenakis's modernism fuses with an urge to create something which sounds as if it could have been written in Ancient Greece. A fabulous example of this is Medea, his scary-sounding yet hugely enjoyable 1967 piece for male chorus and five wind instruments (with the addition of natural rocks and maracas) - a work (setting Seneca) that seems to be imagining what an Ancient Greek performance of the play might have sounded like. It sounds to me harshly modern and harshly primitive at the sound time. The sound and the mood of Medea might well be described as Spartan. There are intriguing touches of Stravinsky (Les Noces, Renard (in the central dance), Oedipus Rex) at times but the freshness and ferocity of the music are pure Xenakis.
I'd second that piece with another of his pieces for chorus wind instruments, the delightful A Colone, a setting of Sophocles this time featuring female voices. Like Medea, it is a direct, modally-tinged work and, also like Medea, has the force of a war-cry. Again, it sounds as if it came straight from Ancient Greece.
The energy of Ancient Greece also seems to pulsate throughout some of the composer's solo pieces, such as the thrilling Rebonds B for solo percussionist (1988). And sounding like the sort of music the ancient Spartans might have written if they wrote ballets, another of Xenakis's wonderful solo percussion scores, Psappha (1875), uses a play of colours, short phrases and rhythms to gripping effect. If you like both of those pieces, please also try the four-movement Pléïades of 1978. Métaux uses a metallic instrument of his own devising to create a hallucinatory effect of bells, Claviers uses tuned percussion to create a complex play of folk-like melodies, Peaux uses drums (and the like) to beat out another of the composer's Spartan ballets and Mélanges combines all the instruments in an impression of organised chaos. I love Pléïades.
The way Xenakis's music spurs the imagination is one of its most winning features. The short 1969 piano concerto Synaphaï seems to project the pianist as an Ancient Greek hero (human and Greek in his occasional zither-like imitations) battling not only against the possibility-defying demands placed on him by the composer but also against harpies, furies and sea-monsters. Again and again great swarms of tangled orchestral writing come to menace the soloist. Midway battle seems to erupt with brass crying out and the hint of a march. The piece has that sort of strange, archaic, epic to its ferocious modernity. It doesn't sound remotely abstract.
Yes, there's so much more to Iannis Xenakis than the application of abstract mathematics. Even his ground-breaking Metastatis of 1954, applying mathematical concepts and Einsteinian physics to music, in part evokes the sound of machine-gun fire evoking the recent war and civil war in Greece. I'd rather you listen to it first without being laden with further pre-conceptions and see what you think before reading my outline of it - which runs as follows:
The first section is largely the preserve of the strings, all of whom play independent lines. From the opening unison on one note grows a huge glissando composed of these independent lines, flecked by intermittent pecks of percussion, climaxing on one vast cluster. This swarms, massively. Percussion tinkle, the swarming begins again and brass join in, causing a fearsome rumpus. Quieter glissandi slide over each other, from which a single chord crescendos.
A few of the solo strings emerge in Webern-like counterpoint, though quickly newer and lighter swarms come to interact with this counterpoint - two types of counterpoint counterpointed! As a result things become far knottier. Drums start to fire at the base of the still-quiet texture.
Huge masses of sound emerge. Brass and percussion play a large part here. They move by each other like giant prehistoric creatures slouching through a barren landscape whose skies teem with insects.
A final glissando gathers strength then resolves onto a single buzzing note.
My last piece in this introductory survey of Xenakis's music is one of his greatest works - the astonishing Jonchaies of 1977. When he began to draw on folk-music his art grew very rich and when it was combined with a Rite of Spring-like fury it grew into the fabulous Jonchaies - a ravishing thriller of a piece. What energy it unleashes! It opens with an upwards-surging glissando then, after psychotic stabs from the strings, an amazingly beautiful thing happens - a folk-melody that sounds as ancient as Plato's beard enters and its composite sound-strands diverge into a delectable smear of myriad melodies. Drums rumble behind this archaic-sounding swarm and a line emerges above the crowd, singing. It is swiftly lost again among the other voices. Others emerge though. The drums return loudly, bringing this teeming chorus to a close. Then the pounding begins...Stravinsky's Rite is reborn, but even the youngish Stravinsky might have baulked at the sheer mercilessness of Xenakis's mass bombardment of the listener's senses, the unrelenting rhythms, the strident sonorities, the searing ambiance. The juggernaut does one huge gear-change but is soon back in the old gear again, pounding, pounding...The music begins to shriek and then to slash as it grows ever more nightmarish. Suddenly the pounding stops and brass consort in mid-air. Gongs splatter amid their agony. Things go quiet but slithering brass keep things sinister-sounding, shrieking breaks out again and drums batter their way to the front. Shivers run through the orchestra and a desperate cry seems to stretch out in all directions. It dies away leaving only a tinkle of percussion then piercing piccolos.
Xenakis was a very prolific composer. There is so much more to discover.