Terry Riley’s ‘In C’ – by all accounts, the most important work in the history of minimalism – has been re-recorded by Portishead‘s Adrian Utley.

Composed in 1964, In C is made up of 53 discrete musical phrases of varying length, which can be repeated as many times as the performers choose. Naturally, performances vary wildly, both in length (the piece can last a matter of minutes of many hours, depending on the ensemble) and form.

Following last year’s walking trail piece, Utley is to release his own interpretation of Riley’s landmark work. In order to put his own spin on the piece, Utley assembled his own ‘Guitar Orchestra’, featuring 24 musicians from in and around Bristol. PJ Harvey collaborator John Parrish is among 19 different guitarists convened for the occasion, with Thought Forms and Portishead sideman Jim Barr among the fellow axemen. The outfit also features four organs and a bass clarinet.

Earlier this year, the group convened in Bristol’s St. Georges Hall to record their version. The results are to be made commercially available on CD in late September, courtesy of Invada. A trailer performance is available to watch below. Utley describes the project as follows:

“I’ve been exploring the sonic possibilities of massed guitars for a while now in various contexts from pure noise to the sacred choral music of Arvo Part.  So it was interesting to see what would happen if we had 20 electric guitars plus organs playing ‘In C’.  It is an amazing piece of writing and original thought.  A new free idea of organised group playing.  The beginnings of what we know as minimalism.”

In C is due on Invada on September 30. A European tour is also promised in the coming months. Riley, incidentally, looms large over our recent interview with Ambient pioneer Robert Rich, who talked us through his legendary ‘sleep concerts’.