Murray McLachlan, Wigmore Hall, London

Murray McLachlan is an energetic young Scot with a mission. He has already made a daunting number of CDs, many of little-known music, but including Beethoven's Sonatas Volume One, and three featuring the music of Erik Chisholm. Chisholm wrote the first comprehensive book in English on Janacek's operas, and had three careers in his 61 years: as a conductor who introduced Bartok's Bluebeard's Castle to this country; as a teacher; and as a composer. Sir Arnold Bax called him "the most progressive composer that Scotland has produced"; less respectfully, he was dubbed "MacBartok", and his Sonata of 1939, with which McLachlan ended the first half of his recital on Sunday, showed why.

Preceding it with Bartok's Out of Doors Suite of 1926 may have been instructive, but it was hardly flattering. Personally, I find many works in this, the "classical" period in Bartok's development, clinical and chilly. But objectively, the music is nothing if not purposeful and superbly well-crafted.

By comparison, Chisholm's four-movement Sonata, which must have lasted all of 25 minutes, seemed in need of drastic editing; the grandiose and densely textured development of the first movement called out for an orchestra, which might have clarified its harmonic sludge. The slow third movement, commemorating the Thetis submarine disaster, was powerful, building up to a tragic climax between icily atmospheric outer sections. But all the movements were shackled to their insistent rhythmic motifs and unattractively written for the piano, with hands far apart, giving a gritty texture with a hole in the middle.

Attractiveness is a quality that Ronald Stevenson, a former teaching colleague of Chisholm's, probably despises. But his short fantasy on themes from Kurt Weill - A Threepenny Sonatina - here having its first performance, was uncharacteristically out to amuse, almost flip. And Kaikhosru Sorabji's Fantasiettina sul nome illustre dell'Egregio poeta Hugh MacDiarmid ossia Schirsopher Grieve MCMLXI was almost shorter than its title, beginning with a flurry of dissonance, then languishing in a narcotic daydream, before an insolently violent ending, as if to say: "So there!"

It was hard to judge McLachlan's playing in these new or unfamiliar works, though he sometimes seemed less than sure of himself in Chisholm's Sonata. But he made good sense of Janacek's Sonata, conveying the evocative quality of the first movement and sustaining the second with a firm sense of its overall shape. Intensity was missing, although that, in a programme demanding so much stamina, was hardly surprising.

At the end of it all, McLachlan still had to climb that musical Everest of the early 20th century, Busoni's Fantasia contrappuntistica. Centred on the unfinished movement from Bach's Art of Fugue, with chorale settings emerging, sometimes to dramatic effect, from clouds of polyphony, Busoni's homage to the greatest composer of our Western tradition fell upon the ears like balm after so much acerbity in the music heard earlier, and McLachlan played it with a real sense of engagement. More than that, in such heavily laden music, one hardly expects.

Murray McLachlan takes his recital to 10 regional venues, starting at Glasgow University on 10 January (www.murraymclachlan.co.uk)