The scene at Damrosch Park last August promised something spectacular: amplifier setups for 200 guitarists and 16 bassists, configured in a horseshoe that stretched along the south end of Lincoln Center, across the front of the park's band shell, and curved up alongside the Metropolitan Opera House. The rehearsals for 'A Crimson Grail,' an epic-scale work by the experimental composer Rhys Chatham, had gone exceedingly well -- first at the nearby Church of St. Paul the Apostle, then, at 1 p.m. on the day of the event, in the park. 'The sound was so fantastic,' Chatham recalled recently via Skype from his home in Paris. 'It took my breath away.' Then came the rain. With an intensity that pummeled umbrellas out of shape, the early-evening thunderstorm -- categorized as a tornado at one point -- drenched the park and miraculously ended just before the concert's scheduled start time. But with water pooled on the pavement beneath amps and power lines, the performance of 'A Crimson Grail' had to be canceled for safety reasons. 'It was one of the hardest nights of my professional career, hands down,' said Bill Bragin, the director of public programming at Lincoln Center.On Aug. 8, in another of the city's remarkable season of free concerts, the plan is to try it all again. But this time there will be risers for the musicians, tenting and a different electrical plan. In addition to the opportunity to bask in a highly unusual concert, the U.S. premiere of 'A Crimson Grail' will offer a chance to witness the homecoming of a prodigal son of New York Minimalism, an art-music composer who has had a tremendous, if underappreciated, impact in the world of rock. After last year's washout, which received a lot of blog attention, word is getting out; if the weather is good, Lincoln Center is expecting a crowd of more than 10,000. There has been only one official performance of 'A Crimson Grail': the world premiere in 2005, a 400-guitar version staged at the Sacre-Coeur Basilica in Paris. (The New York performance will be a version revised for fewer instruments and outdoor acoustics.) That too was a formidable undertaking, though the challenge was more theological than meteorological. 'The mission of the basilique is to have prayer 24/7, so I was in negotiation with the bishop there for three months,' said Chatham, 56, flashing an impish grin into his computer lens. 'I gave him a sample of the music, the quietest sample I could. And he said, 'Oh my God, it's too loud!' And I said, 'Don't worry, Father. I'm going to make music to pray to.'' The final agreement was that each of the work's two half-hour sections would alternate with a half-hour of silence for prayer. Despite a bomb threat during rehearsals, the piece was presented and repeated in this on-again-off-again manner, from 7 p.m. to 7 a.m., at the city's annual Nuit Blanche arts festival. By dawn, Chatham said, the church was still full. A recording made at Sacre-Couer and released on the Table of the Elements label in 2006 is most startling for its timbral beauty and nuance, which often evoke the sound of a string orchestra and choir. Listeners at Damrosch Park can expect a meditative, slowly unfolding work, filled with huge, droning sound clouds that, like a pointillist landscape, reveal great detail on close inspection. It might justly be considered 'music to pray to.' In many ways 'A Crimson Grail' is a logical step in Chatham's evolution. Born in Manhattan, he studied classical music at NYU (flute was his primary instrument) and worked tuning pianos for clients including Glenn Gould. He also worked for, and studied with, La Monte Young, the West Coast transplant whose reductive strategies helped crystallize the Minimalist movement among composers like Terry Riley, Steve Reich and Philip Glass. Soon Chatham joined their aesthetic ranks. Around the same time, in 1971, he became the first music director of the Kitchen, the forward-looking multimedia art space. At 19 Chatham found himself at the center of a nascent downtown scene where jazz players, classical composers and punk-rockers were rubbing shoulders and sharing ideas. One of his great artistic epiphanies came out of this melting pot when, in the summer of 1976, the composer Peter Gordon took him to CBGB to see the Ramones, who had just released their debut album. It was Chatham's first rock concert; he was 23. 'I was looking for a musical voice,' he said. 'I thought: 'Steve Reich uses Ghanaian music, Phil Glass uses jazz instrumentation, La Monte Young comes out of Indian music. I've got to find my own thing.' Then I heard the Ramones, and I said, 'That's my voice.' The next day I got a Fender Telecaster, and that was the start of my long love with the electric guitar.' He worked briefly with a group called Arsenal, to learn rock vernacular. But the first real fruit of his new affair with the guitar came in late 1977, when he developed a work based on overtones created around one note played on an open low E string. Driven by bass and drums, 'Guitar Trio' is a wiry, propulsive and magically shape-shifting composition that indeed unveiled a new voice in Minimalism, and it made an impression on a number of musicians. One was the guitarist Lee Ranaldo of Sonic Youth, who claims he had an ecstatic experience when he saw a performance of the piece in 1979 at the New York club Max's Kansas City. 'It was tremendously liberating to hear,' Ranaldo said in a telephone interview. 'The spirit of experimentation and openness to combining different kinds of ideas around an electric guitar center. What it does psychoacoustically is fantastic. He really tapped into something.' 'Guitar Trio' generated ideas about the power of massed guitars, riff repetition, alternate tunings and overtone manipulation that still resonate in the rock world. Ranaldo said that Chatham's work has had an 'incredible effect' on Sonic Youth, which has been a major force in advancing those ideas. Another force has been Glenn Branca, a musician who performed with Chatham in the earliest versions of 'Guitar Trio' and went on to compose similarly guitar-based pieces -- including a work for 100 guitars, 'Hallucination City' -- to somewhat greater notice than Chatham. (For a while Branca's ensemble also included Ranaldo and his band mate Thurston Moore, who have performed with Chatham as well.) While Chatham has also written for solo piano, for gongs and for brass, 'Guitar Trio' has remained his signature. A CD release of a recent series of revival concerts, which featured Ranaldo and Moore alongside other indie-rock luminaries, is tellingly titled 'Guitar Trio Is My Life!' Yet the sheer scale of Chatham's later works, including 'An Angel Moves Too Fast to See,' written for 100 guitars, and 'A Crimson Grail,' have hooked the imagination of a new generation of fans, some of whom will be performing at Lincoln Center. The ensemble for 'A Crimson Grail' is largely volunteer, assembled through an online application process that encouraged serious amateurs as well as professionals. Musicians will be coming from around the country to play; many are making the trip for the second time. New York musicians will be well represented. Sarah Lipstate, 25, a guitarist formerly with the rock group Parts & Labor who now performs under the name Noveller, will be coming in from Bushwick, Brooklyn, again, along with many friends. Emilie Friedlander, 24, a violinist and music critic from Williamsburg, Brooklyn, will be returning too -- even though by her own admission she has 'virtually no background as a guitarist at all, other than knowing how to hold down a bar chord and sustain a running tremolo for several minutes at a time.' (On the plus side she cites her experience with orchestral performances.) The section leaders, each commanding a platoon of 50 guitarists, include Seth Olinsky, of the experimental Brooklyn-based band Akron/Family, and the veteran composer, bandleader and author Ned Sublette. In addition to the thrill of playing a novel piece of music, the draw for musicians is the opportunity to join a society of kindred players. Despite the rainout Friedlander called last year's rehearsal 'the highlight of my summer' -- in part for the experience of collaborating with musicians young and old, seasoned and neophyte, with backgrounds in jazz, rock, avant-garde and other styles of music. For Chatham, the social byproduct is part of the design of his large-scale works. 'I was originally a wind player in a classical orchestra, way before I ever started playing guitar,' he said. 'So my idea was to create a situation where guitarists could have this experience.' The result is that players meet, network, hang out, share ideas and form a community -- which often continues after the performance ends. 'At one event,' Chatham said, 'the organizer, who was also a guitarist, saw a nice lady playing in his section, and one thing led to another. They married, and their child recently turned 9. So all sorts of good things come out of these events.' 