Daniel Harding's Prom with the Mahler Chamber Orchestra was all about the key of C, the most basic in music. Three works in the major – Schumann's Second Symphony, Mozart's Piano Concerto K503 and Sibelius's Seventh Symphony – were prefaced by a single piece, Mozart's Masonic Funeral Music, in the minor. And it was all done with the mixture of engagement and clarity we've come to expect from this conductor and ensemble.

The first half of the concert was the more compelling, despite Harding's quirky decision to run the Masonic Funeral Music and the Schumann together without a break, an idea that misfired when the audience applauded spontaneously after the first movement.

The latter was one of the symphony's great performances: seething with energy, thrillingly played (the scherzo above all) and emotionally direct without resorting to sentimentality. Schumann wrote the work while recovering from depression, and its detractors, fazed by its therapeutic nature, have argued that his obsessive reiterations of thematic material are slipshod and repetitive. In this instance, however, not a note seemed extraneous, and the whole thing dazzled from start to finish.

After the interval, Paul Lewis was the gracious soloist in K503, while Harding expertly negotiated its sometimes tricky balance between majesty and intimacy, operatic complexity and restraint. In the first movement, Lewis used a version of the big, weighty cadenza prepared for the work by his mentor Alfred Brendel. Sibelius's Seventh, meanwhile, was noble and lucid, flowing organically and seamlessly from its penumbral opening to its calm close. The MCO deploys a smaller body of strings than we usually hear in this work. There were no problems with balance, however, and the playing was exceptional in its beauty and finesse.

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