This year, the Takács Quartet will be a venerable 40 years old. Formed by four students in 1975, only cellist András Fejér remains of the group's original makeup, and violist Geraldine Walther's 2005 replacement of Roger Tapping was the last change in roster. Through all its incarnations the quartet has been repeatedly celebrated for the supreme quality of its playing, including an Order of Merit Commander's Cross from the President of Hungary for each individual member. On Monday night they joined forces with the force-of-nature pianist Marc-André Hamelin for a concert celebrating the sensuous, perfumed and passionate in music, with works by Debussy preceding Franck's great Piano Quintet. What a display of sheer musical brilliance it was! There was no doubt at any point that this was the work of musical royalty; I can say honestly that, try as I might, I couldn't find a single flaw from start to finish. Every member of the group played with unity of intention, flawless ensemble, and an absolute joy in every moment of the evening's music-making. Movement and communication were obvious throughout, and the rapport of the musicians made for a totally engaging, irresistible performance.

If anything in particular struck me about the Takács, it's their absolute comfort with the hierarchy of the string quartet. One has no doubt this is a partnership of equals, but absolute authority emanates from first violin Edward Dusinberre, both in his playing and in his physical leadership. All it takes, should there be any hint of flagging energy levels, is a slight shrug of encouragement, and the group comes alive. Nowhere was this more obvious than in the exposed melodies of Debussy's G minor String Quartet. The whole group moved as one, and dynamic shifts were absolutely overwhelming. Even in the delicate, exposed octave melodies between first violin and viola, where lesser artists might let the ensemble slip, absolute confidence prevailed.

Walther's quirky viola melody at the opening of the Spanish-inflected scherzo was a fine example of the quartet's characteristically wide and highly expressive vibrato. Every phrase was like a breath, with a spontaneity and immediacy that demanded one's attention. Nowhere was this better proven than in the exultant, languid slow movement. The middle section's long-breathed viola melodies were punctuated with chords so open, so glittering, that they sounded for all the world like Vaughan Williams. It was these pianissimo moments, even more than the warm fortes or ferocious fortissimos, that were truly ravishing, capturing the sultry, hazy sweetness of the exotic sun, that darkly seductive note that lurks in the otherworldly harmonies and timbres. Debussy's gently mocking subversion of German formalist procedures was expertly evoked, leading to a glowing finale that left the whole audience beaming.

Authority, again, was the watchword for Hamelin's Debussy Preludes, taking six from Book 2. The Canadian pianist has expressed his preference for the Frenchman's music in interviews, citing a shared interest in making the piano sound like anything but. His touch is miraculous; even pianos seemed to fill the whole hall, and fortes were dizzying with tone, not a hint of harshness anywhere to be found. Hamelin's rhythmic sense is exquisite; tempo was absolute but his way with subdivisions gives the impression of absolute freedom, of absolute expressive control and mastery. The drunken march of “Général Lavine – eccentric” was splendidly characterful, and the madcap crescendos of “Feux d'artifices” utterly breathtaking. Again, though, it's the moments of quiet, where a quasi-Wagnerian 'bed of sound' emerges in the texture, that Hamelin is at his best. So the lopsided, interplanetary waltz of “Les fées sont d'exquises danseuses” or the great, implacable tell of the moonlight in “La terrasse des audiences du clair de lune”; Hamelin's control of every part of the texture and impeccably clear pedalling drew the audience into this uncanny, haunting world.

Franck's world of desire is a much more vivid affair. With its heart on its sleeve, there is very little of the half-light of Debussy. Of course, Hamelin and the Takács Quartet rose admirably to the challenge. Hamelin's awe-inspiring tone finds its natural partner in the golden, soaring cantabile of Dusinberre's violin. That characteristically wide vibrato was ornamented, scandalously, with some very welcome portamento in the first movement, adding interest to the motto theme on its slightly-too-frequent appearances. Overflowing passion defines the quintet and the frenzy of the first movement's conclusion was devastating. The living, breathing immediacy of the group's phrasing made the mournful slow movement truly moving; Hamelin's high chromatic entries were perfectly balanced by the autumnal glow of the strings' romantic melodies, and the return of the motto theme at the end of the third movement was heart-breaking in its melancholy beauty. This was a performance that defied description. By the end of the finale I had closed my notebook, and just luxuriated in the brilliance of the performance taking place before me.