The decision by the DEAF organisers to take electronic music out of the clubs and into more unorthodox venues is increasingly looking like a masterstroke. It's difficult to conceive of a more suitable environment for Decal's moody electronica or Coil's foreboding ambient compositions than the baroque surroundings of City Hall; as the evening progresses, the novel mixture of historical artefacts (paintings, sculptures etc) and cutting-edge sonic experimentation becomes more and more captivating.

Alan O'Boyle gets proceedings underway with a masterful forty minutes of atmospheric, down-tempo grooves, which once again demonstrates that the Decal spin on the ambient style is as inventive and inspired as any of the genre's more exalted international practitioners. O'Boyle's braiding of various disparate strands is subtle and compelling; a touch of Aphex/Polygon Window analogue-bubblebath here, a smattering of Eno-esque urban melancholy there, all topped off with the producer's own winningly idiosyncratic stylistic flourishes.

His set-closing mix of Pan Sonic-style sinister bass pulse and Fennesz-like buzzing static sets the scene perfectly for Coil, never a group to shirk a challenge when it comes to musical innovation. However, even before they play a note, they make an impact. John Balance, though as soft-spoken and gentlemanly a character as one could hope to meet, nonetheless has a disconcerting stage presence; with his druidic beard, unnerving stare and consummately oddball sartorial choices (tonight modelling a dark work-shirt and archaic tie that give him the appearance of a 19th century undertaker), he makes a unique and compelling performer.

Accompanied by Julian Cope collaborator Thighpaulsandra and folk maestro Cliff Stapleton ("the Jimi Hendrix of the hurdy-gurdy," as John describes him), Balance and Peter Chrisopherson navigate their way brilliantly through singularly imaginative ambient terrain; comparisons are very hard to come by, unless one invokes similarly reclusive and iconoclastic experimentalists like The Residents and Boards Of Canada (there is confirmed mutual admiration between BOC and Coil).

Their real secret weapons, though, are Christopherson's visuals; as anyone who has seen his awesome videos for Nine Inch Nails can attest, he has a powerful and distinctive directorial style. At times tonight, such as when one gorgeously dark, pastoral composition is accompanied by shots of autumnal branches swaying gently in the breeze, followed swiftly by a strangely ominous, 360 slo-mo pan of a forest at dusk, the interplay between image and soundtrack is absolutely breathtaking.

The concluding film is a treated montage of psychedelic flames, over which the group strike up a gorgeous hypnotic rhythm, Balance chants, "This is just the way it is" over and over, and a guest vocalist chips in with some eerie, ghostly wails. The previous eighty minutes has charted its way through territory generally referred to as "abstract"; this ventures off out into some place they haven't got around to mapping yet.

More gigs of this vintage, and DEAF is well on its way to becoming one of the highlights of the musical year. Tonight, though, belonged to Coil, who showed that 20 years of pioneering experimentation still hasn't dulled their appetite for deconstruction. Shine on you crazy diamonds.

Stay tuned to hotpress.com for Paul Nolan's forthcoming interview with Coil...