Saturday's Prom, spirited into energetic life by Mark Elder, showed the 150-odd teenagers of the National Youth Orchestra of Great Britain on fine form. Each member should be proud, as should the outstanding musicians who coach them.

The problem is that its annual Proms jamboree is obliged to seek a supersize repertoire. Accordingly, Shostakovich's Symphony No 7, Leningrad, not his best, chooses itself by a load-bearing capacity for multiple woodwind and brass blasting out its noisy rhetoric.

In Prokofiev's Piano Concerto No1, with soloist Alexander Kobrin, this everyone-gets-a-go approach resulted in serious musical misjudgment, like Hamlet performed with two Poloniuses. American Aaron Jay Kernis's light showpiece, New Era Dance (1992), has Bernstein-esque exuberance, but why not commission two short contrasting pieces from an emerging British composer? These fantastic players deserve the best.

Two clarinettists starred in Friday's BBCSO Prom. The phenomenal Kari Kriikku gave a mesmerising account of Magnus Lindberg's Clarinet Concerto (2002), dazzling in its panoply of slides, smears and multiphonics. Then the orchestra's principal clarinet, Richard Hosford, shone in Rachmaninov's Second Symphony, lovingly conducted by Semyon Bychkov. The cheers were explosive.