Prom 23, Royal Albert Hall, London

Swathes of empty seats greeted the Ulster Orchestra for its Prom last Monday night. Youth and new beginnings seemed to be the pegs on which the programme hung. Ian Wilson's 12-minute Man-o'-War, the fourth BBC commission this season, received its world premiere. Wilson is a young Irish composer whose performances in mainland Britain have been largely confined to chamber works in such festivals as Cheltenham and Spitalfields. He is known for writing many concertos – two for violin – and works for cello, organ and piano. This work is his first purely orchestral piece.

The title Man-o'-War has a double meaning: it refers both to the old English name for a naval warship and the dangerous Portuguese jelly-fish. While Wilson has brushed with both Irish and Kosovan politics, having lived in both places, in his pre-concert talk he surprisingly admitted to having not a political bone in his body. Despite this, a heavy hint of the military was felt through the use of bombastic side-drum, and with such an aggressive title it seemed unsurprising that the lower brass, in particular the tuba, should be given prominence. The string texture was occasionally muddied by resorting to quarter-tones, a technique used quite successfully here but risky: the musicians can appear to be merely playing out of tune.

Ulster's principal conductor, the Russian violinist Dmitry Sitkovetsky, looked uncomfortable. He should have been more in his element when he took out his fiddle to perform in one of the youthful Mozart's most tender and beguiling works, the Sinfonia Concertante K364. Some musicians are good at combining the roles of soloist and conductor, but not on this occasion Sitkovetsky. Too often the music's spell was broken by his belief that conducting with his elbow must help matters. His solo viola partner, Nobuko Imai, unencumbered, produced ravishingly beautiful shapes and phrases, in particular subtly colouring and pointing Mozart's sublime slow movement.

Sitkovetsky again took out his fine violin for Arvo Pärt's ubiquitous Fratres, this time in its virtuoso violin guise written for Gidon Kremer. Fratres was Pärt's first attempt at a style, totally at odds with his previous modernist ways, where the sound of cod-baroque is combined with the means of endless repetition; astonishingly, the six different arrangements are each commandingly moving. But Sitkovetsky, while brilliant at times, was again over-concerned with the accompanying strings and percussion, never allowing a sense of real peace to reign.

The last work, Shostakovich's First Symphony, shows youth at its most precocious. The four-movement symphony, sketched when he was not yet 17, teems with ideas, and solos for many of the orchestra's principals. They did well but the evening as a whole lacked lustre.