The second and final instalment of Steven Osborne's survey of Tippett's piano sonatas, comprising the Third and Fourth, was proof of Osborne's stamina. It also demonstrated that, though the composer's voice may not come through as strongly on piano as it does in his orchestral work, these sonatas still deserve performance, given a pianist brave enough to tackle them.

Osborne had again chosen apt works to introduce each sonata, and the Third was preceded by a warm, well-controlled performance of Beethoven's Six Bagatelles, Op 126. The end of the first of these found him carefully shaping two simultaneous melodies at either extreme of the keyboard; the fourth, almost too heavily hammered out in its frenzied early passages, ended in peaceful stillness.

The sonority of the one and the frantic qualities of the other were united at the opening of the Third Sonata, two lines careering towards each other at breakneck speed as if on a malfunctioning pianola. The finale was even more frenetic. The slow movement in between may, perhaps, be too long for the work's balance, but here it was unmistakably its emotional heart, with Osborne's tender playing making the second variation sound like Tippett at his poignant best.

Next came an outstanding account of Debussy's La Cathédrale Engloutie, in which Osborne's precisely judged, almost emotionless playing drove the clanging of the underwater bells to a huge, sonorous climax.

Echoes of those ringing chords returned in Tippett's Fourth Sonata. This five-movement work, more lyrical than the Third but encompassing all its athleticism, seemed to take the composer to the limit of what he could achieve on the piano. In the third movement, central in every sense, it seemed the keyboard wasn't big enough for what he wanted to say, with Osborne covering every inch of it in monumental, clangorous chords. Yet his pacing was sure and, with the closing moments of the meditative finale, this epic piece found convincing resolution.