Tomorrow's concert by Commotio at Merton College Chapel will feature two world premieres, writes NICOLA LISLE

A penchant for plunging boldly into unknown choral territory is the hallmark of local choir Commotio, and their latest concert, to be given tomorrow night in the exquisite setting of Merton College Chapel, may arguably be their most daring yet.

Two world premieres, two UK premieres and a centenary tribute are dovetailed neatly into an exceptionally well-balanced programme, which, if previous Commotio concerts are anything to go by, will showcase the choir's full range of vocal dexterity and virtuosity.

One of the world premieres, by the London-based composer and teacher Richard Allain, was written for Commotio's forthcoming CD of music for choir and cello, and is a setting of Shelley's poem Night. What made him choose this piece?

"Matt Berry, conductor asked me to write a piece for the CD and as there's going to be a good deal of sacred music, I wanted to complement that with a secular text. I was looking for a piece that was fairly substantial, and with the Shelley, the beautiful word painting was very appealing.

"Writing something for performance in this building with its marvellous acoustics, but also for the recording in June, needed to be something that lends itself to that environment."

Listening to the choir rehearsing last week, I quickly became aware that this is exactly the kind of music that these singers perform best, with its rhythmic variations, dissonances and soaring soprano lines. The ending is particularly beautiful, as the singers move into separate groups so that the sound comes from both ends of the chapel.

Richard said: "For most of the piece, up to that point, the choir are treated as a whole unit, with one or two divisions of the music within that theme that Shelley sets up.

"For me, I read into it something of that kind of English temperament, the kind of lament you see in Elizabethan lyrics, while the bass is an evocation of Purcell.

"For the end, I split the groups into three, so there's a solo quartet and two SATB choirs. We aim, with the Coda, to have waves of music. It works beautifully. The expressive quality of the voices is perfectly mixed with the cello."

So how did it feel to hear his piece lifted off the page for the first time?

"It's a delightful experience with a good group. I thought the rehearsal tonight went fantastically well. The first thing is to find the notes - that's always the hardest thing. For me, the starting point of a piece of music is to imagine the sound growing. The process for me is crafting that in with the ensemble you're writing for."

The other world premiere is Futility, a setting of Wilfred Owen's poem by local composer and Commotio member John Duggan. "I'm always looking for texts to set and I think he's an outstanding poet, so I thought he'd be a challenge," he said. "I didn't realise quite how much of a challenge it would be. With some texts, I can almost hear the notes coming off them, but this isn't really like that, because he has so many internal rhythms and relations between the words. So this is probably the most difficult thing I've attempted so far.

"I'm very passionate about Owen. Some people say he was the greatest poet since Keats, which is quite a hard act to follow. But poetry generally is an inspiration to me and I write a bit myself."

John's broad musical tastes, which range from early choral music and classical music to rock, folk and reggae, inform much of his own music.

"I'm definitely into very early music, so I love to write contrapuntal-type textures, but also from playing drums and percussion I'm very interested in rhythm.

"I think the outstanding composers of the last 100 years have been rhythmically skilled. Stravinsky is an obvious example, but also Britten and Bartok. There is a very strong rhythmic content to their music."

Like Richard, John enjoys hearing his music brought to life by the choir.

"It's a mixture of exhilarating and nerve-wracking," he said. "I'm a bit of a perfectionist, so I know what it sounds like in my mind.

"But I haven't had my music performed that much, so I'm just grateful that Futility is being performed. I'm looking forward to it."

Elsewhere on the programme, Commotio pays tribute to the unjustly neglected Anglo-Irish composer Elizabeth Maconchy, who was born 100 years ago in March. Maconchy's Variations on a Theme from Vaughan Williams's Job' is her own tribute to her former teacher and mentor who, along with Bartok, was one of her main influences.

There are also the UK premieres of Thomas Jennefelt's Vinamintra Elitavi and Jon Mostad's O Sing to the Lord, as well as pieces by Geoffrey Bush and Eric Whitacre.

Commotio's Music for Remembrance and Oblivion is at Merton College Chapel tomorrow at 8pm. Tickets are available from 07711 980279 or info@commotio.org. For more information about Commotio and their forthcoming CD, visit www.commotio.org