Not all were solved for this celebratory performance marking English Touring Opera's 30th anniversary. The small chorus (ten women and seven men including the singers of the comprimario roles of Clotilde and Flavio) is behind the orchestra; the soloists stand at the front of the stage with their backs to the conductor – James Hurley for this captioned performance.

This means that the menace of the Druid priests and Gallic warriors comes over as somewhat muted. While the principal characters are singing either by themselves or with just one other person, there's little difficulty but not being able to see the conductor does lead to a certain untidiness with entries in the big concerted numbers which conclude both acts.

For the most part, acting is confined to small gestures and left to the voices to communicate emotion. The men are formal in black and white. Norma shimmers in majestic purple and Adalgisa in dark blue; the two women are equal in vocation, love and self-sacrifice but not in status.

Yvonne Howard in the title role produces a voice of extraordinary flexibility moving seamlessly between its upper and lower registers and with meaning in every sentence. The Act Two duet with Alwyn Mellor's Adalgisa "Mira, o Norma" deserves its ovation. Mellor's also has the sort of flexible voice which can encompass elements of the mezzo as well as soprano ranges thus adding depth as well as the required decoration.

In the varied ranks that make up tenor heroes, Pollione is an ambiguous one, a sort of Pinkerton precursor. Justin Lavender goes at him full throttle, with "Meco all'altar di Venere" less successful than the later duet with Adalgisa "Va, crudele" and the trio with Norma and Adalgisa "Oh non tremare". Piotr Lempa's Oroveso makes a firm impression with his invocations to the warriors in both acts.

Reviewed at West Road Concert Hall, Cambridge

- Anne Morley-Priestman