No matter how well I imagine myself to know a piece, I always strive to attend pre-concert talks. Something new usually emerges, occasionally something pivotal. RSNO violist Katherine Wren mentioned Messiaen's admiration of Stravinsky, stressing similarities between his own Turangalîla-symphonie (1946-48) and Stravinsky's Petrushka (1910-11). The prominence of piano is certainly striking. What had remained hitherto hidden from me were similarities in the writing - specifically the bitonal theme for clarinets. Stravinsky employed it to highlight a protagonist/antagonist relationship. In Messiaen's Tristan-inspired, 10-movement symphony, bitonality seems a reminder of our perceived separateness, which love, art and religion seek to transcend - through less permanent interpretations of “death of self” than Tristan and Isolde.

The title, an amalgam of Sanskrit words "turanga" and "Lîla" fuses notions of tempo with rhythmic play and creation. It's really a cosmic love song. Wren's talk also conveyed her brimming excitement at the thought of playing this work. The unpopulated stage looked awe-inspiring before the musicians assembled. The programme boasted 107 names plus conductor and soloists. Immediately encircling Principal Guest Conductor Thomas Søndergård was a concertante of keys: piano, celeste, keyed glockenspiel, vibraphone and ondes Martenot. Their percussive potential was reinforced by a distant, eight-man hit squad in the percussion section, whose armoury ranged in size from occasionally insistent wood block, through quickening side-drum, to deafening tam-tam. Messiaen, clearly not one to look a gift horse in the mouth, made the most of Koussevitzky's generous post-war, pre-crash commission, which allowed complete freedom of subject, style, forces and duration.

The Introduction promised a work of extremes. Markus Bellheim and Jacques Tchamkerten very quickly explored opposite ends of piano and ondes Martenot respectively. Extremes of orchestral pitch were soon juxtaposed in Toby Street's wonderful high trumpet notes and the muscular gravitas of the excellent trombone section's “statue theme”. This is one of four themes which are recycled to bind the many diverse elements of this essentially non-developmental symphony. Although capable of staccato, the ondes Martenot (named after its inventor, Maurice Martenot) is famed for glissandi which here reminded me of The Mighty Boosh and Star Trek. Any love theme worth its salt benefits from soaring and what better instrument than this, supported by lush RSNO strings, to clinch the mood.

However, as David Kettle stressed in his fine programme notes, the second movement, “Chant d'amour (Love song 1)”, also features “a spiky dancing melody”, hinting at love's dangers. Following an unashamedly Hollywood triumphant restatement of the love theme, piano and strings brought this movement to a virtuosically crashing end. A work of this cosmic nature should, and does, contain everything: birdsong, dance band-style parallel harmonies (occasionally resembling laughter), simplicity and multi-layered complexity, tranquility and joyous bedlam. Hearing the RSNO make such ready sense of this diversity was thrilling.

Watching Søndergård's technical approach was fascinating. There seemed to be two distinct conducting styles. In those sections which I imagined to convey the impersonal, mechanistic cosmos which serves as backdrop to the elements of love and play, he employed a very distinct, almost edgy beat. Hands were held high for the benefit of the distant percussionists. In more fluid passages, his arms were much more relaxed, almost at swim, encouraging the orchestra with what felt like “let's enjoy this” gestures. The sixth movement,  “Jardin du sommeil d'amour (Garden of the sleep of love)” was simultaneously hypnotic and intriguing. To convey the idea of residing at peace in such a scene, Messiaen avoids any hint of pulse and therefore awareness of passing time or impression of forward propulsion. Yet the performance has to avoid the common diagnosis of lacking pulse - being dead. This was beautifully done. Messiaen's beloved birdsong chirped unhurriedly from the piano while, over a lawn of love theme on ondes Martenot and strings, Katherine Bryan's flute and John Cushing's clarinet wafted engaging melodies of unambitious contentment. The ethereal contribution of celeste perhaps hints that such a garden is not readily to be found on Earth.

Two movements stand out for unbridled joy: the fifth movement, “Joie du sang des étoiles (Joy of the blood of the stars)” and the closing finale. The frenzied piano cadenza in the former was fantastically spirited, calling to mind the explosive power of such avant-garde improvisers as Cecil Taylor. This was all the more impressive as Bellheim's playing in the tutti sections was had been no less frantic. Following the lengthily sustained final chord, the Usher Hall erupted into heartfelt thanks. Included in the customary and well deserved acknowledgements was a very touching gesture: Søndergård, hand on heart, bowed long and deep to the orchestra to thank them for an outstanding performance. It seemed that, like us, he'd had the time of his life.