With a range that sees to encompass everything from Lully to Lachenmann, François-Xavier Roth is hard to categorise as a conductor. For his prom with the SWR Symphony Orchestra Baden-Baden and Freiburg, though, he was very much in 20th-century mode, and devoted the first half to continuing the season’s 90th-birthday tribute to Pierre Boulez.
‘... explosante-fixe ...’ is one of the family of works that was derived from a brief tribute to Stravinsky, more a compositional kit than finished piece, which Boulez composed in 1971. Typically, though, ‘... explosante-fixe ...’ still took more than 20 years to reach its present form, as a work for solo flute, electronics and ensemble.
It is, though, one of Boulez’s most seductive pieces, radiating out from the solo flute, played by Sophie Cherrier, through two other flutes that shadowed her to the wider ensemble and then projected around the auditorium via the electronic transformations of their sounds. It creates a vast web of musical echoes and reflections, the apotheosis of the melisma, lasting just over half an hour, with brief static interludes, during which the auditorium lights were dimmed, separating the three parts. The serene yet hyperactive Cherrier, who took part in the first performance of the work in 1993 and seems to have been playing it ever since, while the SWR Experimentalstudio took charge of the electronics.
Roth’s meticulous care for textures paid dividends in the other two modern classics in his programme too. Ligeti’s Lontano, terrifyingly restrained yet totally compelling, preceded Bartók’s Concerto for Orchestra , in which Roth concentrated on rhythmic energy and clarity. It was never heavy-handed, and any temptation to turn it into an overmanicured orchestral showpiece was resisted.
• Available on BBC iPlayer until 25 September. The Proms continue until 12 September.
