The opening weekend of the 2015 Proms included a performance of Beethoven’s Ninth. It needs an occasion, and the excitement surrounding the new season, the hordes converging on the hall, the ticket touts, the summer dresses, the chatty promenaders, all created one. The evening was significant, too, for being the City of Birmingham Symphony Orchestra’s last concert with their music director of seven years, Latvian conductor Andris Nelsons who is off to America. The omens were good. OK, so it was not quite the opening night, but almost as good as.Perhaps this slight relegation deflected concentration a little. Even the merest hint of routine in so familiar a work can make the mind switch to autopilot. The first movement worked well with the tantalising introductory bars diving s