Imagine swimming across the Dardanelles.

The narrow strait in north-west Turkey divides the Balkans from Asia Minor, connects the Aegean in the west with the Sea of Marmara in the east – it's just a mile wide in places, but riddled with undercurrents and passing ships. No easy feat, then, and not an obvious way to raise funds to commission a new piece of music. But when Charles Chochrane braved the crossing last year, his swim not only paid for a new commission, but also triggered the inspiration behind the music.

The commissioning ensemble is JAM – the John Armitage Memorial, named in honour of a music-loving advertiser who died in 1998. Set up by John's son Edward, JAM commissions new work every year, always for the same line-up of choir, brass quintet and organ. Partly that combination is because Armitage was a trumpet player and loved the effect of brass, voices and organ ringing out in church acoustics. There's also a practical reason, to do with creating high-impact new repertoire choral societies can perform without needing to hire expensive orchestral forces.

Loading article content

This week and next JAM teams up with Scotland's Red Note Ensemble for the first time to give a series of six concerts in Edinburgh, Glasgow, St Andrews and Aberdeen. Together they've devised two programmes. In one, Pergolesi's resplendent Stabat Mater for soprano, countertenor and strings, sits alongside Scottish premieres of works by Judith Bingham (Jacob's Ladder and The Hythe). In the other programme, the university choirs of Edinburgh, Glasgow and St Andrews combine – the same massive joint forces that premiered Paul Mealor's best-selling Now Sleeps the Crimson Petal (a JAM commission) in 2011. This year they sing music by Britten, Kenneth Leighton, Rory Boyle (Tallis's Light, a ferociously bold reworking of Tallis's motet O Nata Lux) and new work by the latest recruit into the University of Aberdeen's composition faculty, Phillip Cooke.

And there's Body Water, written by former Glyndebourne composer-in-residence Julian Philips and librettist Simon Christmas in direct response to Cochrane's Dardonelles swim. "Our commission also timed with last year's anniversary of the sinking of the Titanic, so we wanted to reflect the experience of being surrounded by a large body of water," Philips explains. "We asked Charles to write down his thoughts as soon as he came out of the water, then revisit them a couple of weeks later. When he sent us the pages we didn't lift his words directly into the text, but they did provide a trigger."

So what did Cochrane's post-swim scribbles consist of? "A lot of thoughts about what his mind was doing during the event. Rather than emotional or physical descriptions he was interested in his own thought process."

Philips and Christmas were keen to avoid creating a literal descriptive work, and translate Cochrane's personal challenge into a work with a universal impact. They crafted Body of Water as a song cycle that becomes a choral piece, opening with a single voice singing about remembering and closing with the choir providing a pool of words. "It's about travelling backwards from a memory to reliving event," says Philips.

"I don't think we conjure up the swim with onomatopoeic sounds of lapping water or anything like that. The experience is more abstract, created through shifting chords and swells. Spacing is important, too, because we'll arrange the musicians and singers so the audience is immersed in the sound. The effect will be dreamlike and ambiguous."

A challenge that comes with JAM's commissions for choir, brass quintet and organ is how to create new sounds for the combination. "There's a long heritage of sacred repertoire for this line-up," says Philips, "and frankly much of it sounds alike with typically ornate organ writing and blazing brass." That's especially true when it's performed (as it normally is) in the wash of church acoustics. Divvying up the performers around the venue is a way of "exploding" the forces: the audience feels immersed in the sound, and the thick textures are spread out. So far the strategy has worked, says Philips. "At last year's premiere of Body of Water at St Bride's Church, London, I was pleased by the sense we gave of the individual versus something enormous. The single voice becomes subsumed into the breadth of the choir. And that can be a really powerful effect in church acoustics."

JAM and Red Note Ensemble starts at Holy Trinity Church, St Andrews, tomorrow. Visit or call 0800 988 7984.