The launch of the 2015-16 BBC National Orchestra and Chorus of Wales season began with an intriguing concert combining, what for some would be, the popular and the unfamiliar. A concerto by Huw Watkins flagged up his position as composer-in-residence and Rachmaninov's choral symphony (making a welcome change from an orchestral symphony) formed the lesser known works of the evening. Borodin’s rousing Polovtsian Dances and Elgar’s popular Cockaigne, however, were not quite enough to draw the crowds on a night when Handel’s Orlando and a recital of Shostakovich’s string quartets could also have been heard in Cardiff. No matter that there were some empty seats, this quirky programme had some great moments  – not least in a marvelous account of The Bells.

The evening began with Stravinsky’s Fireworks – a short and brightly scored work from 1908 intended as a gift for the wedding of Rimsky-Korsakov’s daughter. Under its principal conductor Thomas Søndergård, the BBC National Orchestra of Wales had no difficulty in conveying the work’s sense of celebration but this account needed more cohesion to convince me that Stravinsky’s early trifle makes a good concert opener.

Another early work followed in the shape of Huw Watkins’ five-movement London Concerto – a triple concerto scored, unusually, for violin, bassoon and harp soloists and originally conceived in 2005 for the centenary of the London Symphony Orchestra and three of its principal players. It began with an arresting duet for violin (Malin Broman) and bassoon (Rachel Gough) and progressed to some equally characterful writing for the orchestra. Two inner movements for orchestra alone provided plenty of dramatic activity and, in the second its wild beauty was realised by the jagged phrases (akin to bird-calls) of piccolo and trumpet. Watkins’ gave more lyrical opportunities for the soloists in the central Lento in which Hannah Stone (harp) came to prominence. The concluding Allegro provided further evidence that Welsh-born Watkins, and recently appointed composer-in-association to the BBC National Orchestra of Wales, is one of the most engaging composers working in Britain today.

The Polovtsian Dances is probably the best known passage from Borodin’s incomplete opera Prince Igor. His appealing melodies, energetic rhythms and colourful orchestration make these dances easy to like but here, despite an abundance of enthusiasm, there needed to be a better balance between choir and orchestra and a far clearer delivery of the text, much of which was frequently lost beneath instrumental weight.

After the interval things improved considerably with Elgar’s wonderful depiction of London in his concert overture Cockaigne. Elgar would certainly have recognised this account but, judging from his two recordings of the work, might have considered this performance rather too well behaved. The sense of reckless exhilaration heard in Elgar’s version was missing here, its “stout and steaky” earthiness tamed by a rendition in which Søndergård seemed eager to collect a health and safety certificate. Climaxes were exciting, but tension not always sustained.

It was in Rachmaninov’s choral symphony The Bells where the combined forces of choir, orchestra and three soloists really began to cohere and excite. John Daszak (replacing the indisposed tenor Misha Didyk) brought tremendous authority to the loose translation of Edgar Allen Poe’s poetry and his final top A flat towards the end of the opening movement was thrilling. Anastasia Kalagina (soprano) sang with beautifully poised phrases although her “tender dreams” conjured by the poet could have been sung with even more passion. In “Loud Alarum Bells” the chorus responded with great vigour to their “tale of horror” and their demonic pleas rang out with fierce conviction. The best was served at the end in “Mournful Iron Bells” where, in addition to a delicate cor anglais solo (Sarah-Jayne Porsmoguer), there was Mikhail Petrenko’s sonorous bass - a voice so cavernous you could walk through it. Soloists, chorus and orchestra were all superbly focused under Søndergård’s direction, and if the programme’s first half didn’t quite gel then the second generated much more promise for what was the start of this conductor’s fourth season with BBC NOW.