A MAJOR new Passion oratorio in any genre is something to celebrate. The nave of Wells Cathedral was packed for Omega and Alpha, a much-heralded new work of almost 90 minutes by Martin Emslie.

Is it a success? There was much for a supportive audience to applaud - not least a shivering performance by the three excellent soloists and chorus alike.

Emslie, an experienced choral director and thoughtful composer, has set out to produce a full-scale work along the lines of the Passions of Bach and his era, exploring a range of styles, and yet still delivering something musically consistent, intense, and appealing.

Although the work provided challenges for the large amalgamated chorus, drawn from Castle Cary Choir, All Saints' Church Choir, the Oakfield Choir of Frome, and Wincanton Choral Society (Somerset stalwarts all), Omega and Alpha is very singable. So it will travel, and deserves to.

I itemise those choirs because - especially when singing alongside the soloists - they performed vividly. This was exciting singing, highly motivated, strong in attack, varied and sensitive in dynamic, and well rehearsed.

Emslie has skilfully generated a modern equivalent for the Bach chorale. His enterprising pacing of these items, and the chorus's responsive delivery, were exemplary.

Whether you think that the work deserves to travel may depend on your view not just of the music, but also of the often splendid text - by the composer, I take it. This contained some nuggets (here is a Passion for the 21st, if also 19th, centuries), as well as a few more bits thin on poetic flair. Frequently, it hits highs: for instance, the intense extended passages (akin to the treatment in Bach's St John Passion) for Pilate, sung by the magnificent bass-baritone Gerard Delrez, who was terrific also as Judas (allotted almost as much space as in Elgar's The Apostles) and St Peter.

Much of the music is on a par with musicals: the Holy Week story told through a prism of Les Misérables, say, or Godspell. Bearing this in mind, it works well. There are intermittent banalities early on - the rather vapid music of the opening section (of four), a series of twisting chord-splurging harmonies, adds up to not much - but soon it all picks up. This is true, even given the much-repeated "This is my predicament, Knowing what to do. Where will the future take us, And can I see it through?" - platitudes that even a 14-year-old might find inept.

It held up, and the whole evening came off, because of the soloists - and largely the extraordinary quality and musicality of the young tenor who sang the part of Jesus with such personality, weight, and adeptness that every phrase gained import and intensity. His high notes - to an effortless top B - were wonderful.

Here was a young person's Jesus, a Jesus Christ Superstar figure, but presented without hype or saccharine. Emslie has given Jonathan Ansell, his youthful soloist - once part of the pop-opera group G4, scorching to celebrity on The X Factor, but now so much more than that - a role that really tests his talents.

Ansell took the bull by the horns: he gave his all, and every bit of it counted. Tiresomely, the soloists had microphones: Ansell has no need of that. His voice carries; it is well-supported; pearl after pearl, he has all the gifts of a classical singer. We heard none of the strainings common in the crossover world. He could take on anything: Mendelssohn, Dvořàk, and Vivaldi are all his; and Lloyd Webber, too. But what he captured, and what mattered, above all, was the spirit. The Gospel story, in all its poignancy, beamed through him.

He had a rival. Marta Fontanals-Simmons, the top-notch mezzo-soprano who tackled Emslie's often super recitative and aria work in both mezzo and soprano register, was a delight to hear (again with unnecessary amplification). Often she acts as narrator: another nice original touch in this tangibly expressive oratorio. Her enunciation was stupendous. Her rich tones put me in mind of Sarah Connolly, Janet Baker, and other greats. What a thrill, but not a surprise, to encounter three soloists of this calibre and mettle in this cathedral, whose musical standards are currently second to none.

If I make Omega and Alpha sound a mixed bag, this is because it is. But at such a magnificent performance one forgave almost anything - except some ghastly tuning in the wind and strings (lower, especially) from the modest-sized orchestra in the earlier part of the evening. At those points, omega for them. Alpha for the brass and percussion.