Burt Bacharach strolls onto the Festival Hall stage like he's stepping on board a yacht, the brass buttons on his blazer gleaming in the spotlight. A brief pause to acknowledge the applause, then the captain takes the helm of his Steinway to steer his crew smoothly through a half-century of hits.
The accent throughout is on smooth, remarkably so given the complexity of his material. Bacharach's songwriting is so sophisticated - he reveals that before he found his métier, he studied to be a classical composer under innovative modernist legend Henry Cowell - that in order to smuggle his outré chordings and complex rhythm changes into pop required a special genius for arrangement. It's evident tonight in his distinctive instrumental combinations, particularly in the wind section, whose two players change instruments several times in each song, shading material so it slips down nice'n'easy: the blending of flute and flugelhorn for the strolling motif of "Walk On By" is simple but stunning, while the dramatic, roller-coaster sweep of "I Say A Little Prayer" is artfully encouraged by the pairing of alto sax and flugelhorn.
Likewise, the way he condenses the string section down to synthesised strings, with just a single violinist to lend authentic polish, is a brilliant lesson in the logistics of modern concert performance. Bacharach himself doesn't "do" much, but he's the calm centre of a cool tornado of activity. A silver-haired elfin genius hunched over the piano, he restricts himself to just a few abbreviated hints and accents, rising frequently to cue his seven-piece band through myriad changes.
His own vocal efforts are similarly confined to a few songs chosen to fit his weary croak, most effectively a moving "Alfie"; instead, a trio of singers (Josie James, Donna Taylor and John Padano) front them, in the way that Crosby and Sinatra once fronted the Whiteman and Dorsey bands - and just as skillfully. It takes three to cover the diversity of emotional colours in Bacharach's back catalogue: an opening medley of '60s hits whisks through half a dozen undisputed classics, and doesn't even skim the surface of his extraordinary career.
Later on, a comparably top-notch medley of film songs confirms that he was as ubiquitous a presence in '60s movies as John Barry; while another medley of his earliest hits, somewhat lacking the jet-set elegance of his later oeuvre, even finds space for the kitsch sci-fi novelty "The Blob", theme song from Steve McQueen's screen debut. "Steve's career managed to survive it," notes Burt, wryly. "So did mine." And how.