Andrew Ellis is no stranger to welcoming radical musical-arts projects to his adopted hometown of Liverpool. Under the nom de guerre Samizdat, the city has welcomed and co-opted experimental musicians of a standard rarely equalled in other Northern English cities. His most ambitious project, a performance of Rhys Chatham's 'A Crimson Grail', has just taken place at Liverpool's Anglican Cathedral, featuring the combined talents of 100 guitarists and 8 bass guitarists. The performance was monumental in every sense of the word. Ellis explains the earliest origins of the hook up:

"In 2010 I was part of a great scheme run by PRS called New Music Producers PLUS which pairs independent producers and promoters with arts organisations to work together on building partnerships and helping the producers to gain experience of working with larger organisations.

"It was a really enlightening experience and total privilege, the other producers were predominantly older and more established than myself and I had to make the move from putting on weird noise and rock shows such as Charles Hayward, Daniel Johnson, Liars, that kind of thing, to putting together something befitting of the Bluecoat, the beautiful Georgian arts space I was working with.

"I've been a huge fan of the whole 80's No Wave scene for some time now and I didn't want to stray too far away from my roots so, with the aide of an events team, I decided to bring Rhys to Liverpool to perform his pieces 'Die Donnergotter' and 'Guitar Trio'.

"The performance was received with such praise, and with Rhys being a total joy to work with, I promised that if the opportunity arose I'd get him back to Liverpool as soon as I could."

In July, an open call went out for volunteers; 'A Crimson Grail' would be recreated as part of the city's Biennial Arts festival, which runs from 15 September to 25 November in dozens of venues across the city centre and outlying areas. As Ellis explains, previous experiences of working with the Biennial organisers had proven fruitful:

"I've always enjoyed Liverpool Biennial. Two years ago I helped programme Ted Reiderer's Never Records installation, bringing bands into a derelict club space and cutting their sets straight to vinyl, creating an Alan Lomax-esque library of a particular time in a particular place, so I was keen to get involved this time around.

"The Biennial's new Artistic Director Sally Tallant was previously the Head of Programmes at the Serpentine Gallery, where she brought everybody from Four Tet to Charlemagne Palestine to the space, so we got on instantly and after a short conversation decided upon Chatham's masterpiece 'A Crimson Grail'. The planning process itself was logistically challenging, and far too boring to print. It mostly involved a hell of a lot of emails to-ing and fro-ing between the Cathedral, Rhys' team and the 108 guitarists."

Fittingly for such a monolithic work, 'A Crimson Grail' was commissioned by the City of Paris as part of La Nuit Blanche Festival in 2005, to take advantage of the iconic Sacre-Coeur Basilica's 15-second reverberation. Recordings made from the first performance of the work testify to the triumph of Chatham's transformation; individual representatives of the most everyday of contemporary musical instruments multiply and coagulate into a morass of cloudlike formations. From the off, Ellis was under no illusions as to the scale of the task the organisers faced:

"The call-out itself was probably the most exciting part of the process, upon announcing the show we were inundated by hundreds of applications from guitarists as far afield as Buenos Aires; that's when I started to really understand how important and magical the performance would be. After we had all of the performers confirmed and in place we began sending out scores to each individual guitarist with a letter from Rhys explaining the nature of the piece. This gave the guitarists the background knowledge to begin to learn the piece.

"Upon arrival, Rhys and his concertmaster David Daniell met with the section leaders to work on the conducting process for two days prior to the rehearsals. The piece is in the most part more about the conductor's cues than the score itself. The role of Rhys was to direct the section leaders individually, who would then pass on that information to the guitarists. As you could see in the performance, there were some slightly unconventional conducting techniques, but when you've got so many guitarists, each needing individual directions, you have to think outside the box a little. The piece is split into numerous different Alto, Bass, Soprano and Tenor sections, sat in amongst each other so that no member of any particular section is sat next to another playing the same part. Once rehearsals began, with the ensemble first, the performers were split and tutored separately by part, then on the following day by section. It wasn't until the dress rehearsal that everybody came together, and not until the actual performance that the whole piece was played through."

Liverpool's Anglican Cathedral could almost host the last stand of Christianity following some imagined future war. Unseen from its approach the wide, moat-like graveyard that surrounds two sides of the edifice provides the visitor with a terrifying perspective to this great stele of Scouse faith. Erected in Woolton sandstone, the building is a deep red-orange, marking the horizon for miles around. On overcast days, from a distance, it presents a gloomy aspect. Inside, however, the building's relative modernity becomes its greatest asset. Many tourists and younger locals-alike assume that the building is much older than its 34 years. Compared to the radical 'wig-wam' structure of the nearby Metropolitan cathedral, the Anglican's facade could almost be mediaeval.

On the evening of the performance, crowds streamed up the hilly approach more than an hour before the show was due to begin, filing up the stone steps, passing by Tracey Emin's neon installation 'For you' and packing the neatly spaced rows of seating beneath the great building's apex. The 'orchestra' were barely distinguishable from the mass of spectators; the only clue to their part in the show was a linear white-shirtedness, and the ever-present guitar accessories. Amps formed an honour guard around the auditorium, with five podiums for the conductors.

Half an hour before the show was scheduled to begin, standing room only was available. Ten minutes after the scheduled start time, crowds were still being positioned. A humbled, departing Dean explained that it was wonderful to see the building packed to the rafters for his final week in the job.

Ellis explains his emotions at seeing the crowds gathered to witness the performance:

"I was in total shock, I understood that the piece would draw attention from music and arts fans alike but had no idea that it would attract such attention. It was wonderful seeing such a crowd congregating together to witness something so beautiful, many with no particular idea of what the piece was about, just turning up to experience something that many would not and will not have the chance to see again. I made the call to make the performance first come, first served and was devastated for those who could not get in, hence the conscious effort to thoroughly document the piece.

"Though some of the guitarists are well-known there are no 'celebrity' guitarists in 'A Crimson Grail', a friend described, aptly, that the ensemble is like a swarm or a bee colony, each guitarist playing an equally important role for the greater good of the piece. With this in mind that's why I decided to make the piece first come, first served with no guest-list: equality is inherent in the piece and I wanted the door policy to reflect that.

"Upon talking to some who didn't make it they understood the reasoning, though I still felt a little gutted for them. I read a tweet from somebody who couldn't make it which read something along the lines of 'I've never been so happy to not make it into an event, the number of people showing interest in left-field music and arts is hugely encouraging'.

"I wish people turned out like that to all of my shows, it was a struggle fitting in so many extra people into the space but there was something incredible about having so many people crammed into every possible space in such a monumental building."

And so it began, and ended. Trying to describe the performance itself would inherently do an injustice to it. The most comparable experience I can point to would be an installation I saw at the Tate gallery in St Ives. The artist had filled the main viewing space with white balloons; as visitors pushed their way through the work, static electricity popped between them. The viewers of the piece literally became 'charged' by it. People were laughing hysterically, kicking the balloons and becoming disorientated by the glare of white, refracted light. 'A Crimson Grail' was like that, and nothing like that.

It had its moments of quiet contemplation, when the greatest attention was paid to the individual conductors and their varied gestures, and to Chatham and his myriad of bizarre hand signals. Swells of sounds which weren't quite believable as issuing from guitars would rise and fall, the four sections of the orchestra invoking column-like chords and atonal screeches. The final, triumphant chord progression eventually evaporated into a cacophonous mess of spectrum-wide tones. Throughout the performance, I could see Ellis's reticent figure leaning against one of the great columns, an unreadable expression on his face. Afterwards, I asked what emotions were going through his head in those final, overwhelming moments.

"Exhaustion, relief, ecstasy, sadness that the experience was over after a year or so's work. As with many in the audience, I had been completely taken in by the piece. It is one of those works that just washes over you like a tidal wave. I wish I could have got a spot in the centre for the perfect sound, but I'd have been a hypocrite if I had saved myself a space to sit down over a member of the public.

"The public reaction has been incredible. More than anything, it was the night after the performance when it finally began to sink in what had taken place. It was a real honour to work with Rhys, his team and that incredible group of guitarists, we became a really tight-knit group by the end of it. Afterwards, myself and Rhys had some beers and promised to work together in the future, we've become good friends as has everybody working together on this piece. I'd love to bring everybody back together for another work in the future.

"I suppose the main reason I stopped doing 'normal' shows was because I wanted to really do something special, something people will never see again and I think that was the case with 'A Crimson Grail'."