On St Patrick's Day, 2010, following a night with Paul Brady and the Ulster Orchestra which members of Horslips attended, that band were made an offer by Declan McGovern, then BBC executive producer of music. Multi-instrumentalist Jim Lockhart and bass-player/singer Barry Devlin presumably (it's nearly always Jim and Barry) enthused about the Waterfront gig, remarking how "light on its feet" the orchestra were.

McGovern then had an idea, as the band recall in the liner notes to this thrilling new CD. " Well, why don't we do something with you guys? "Us guys" thought about it for about two minutes before saying an emphatic "yes," writes, well, Jim or Barry.

What eventually made it on to the record was the music best suited to orchestral rigour and complexity - the band's symphonic sequences from The Táin and The Book of Invasions albums, aranged by Irishman Brian Byrne. (Byrne is, of course currently making impressive waves in the US as an orchestral arranger.)

The Power and the Glory doesn't need an orchestra - it's powerful enough on its own - but it is interesting to see how it gains a new oomph in its intro, courtesy of the 69-strong orchestra. Brass and sweeping strings lend a kind of bold mastery.

Trouble with a Capital T gains smoothness and richness, and those glissando strings don't muscle in on the core riff. (More 'bottom' or bass in the mix, though may have been required, but that's a mere quibble.) Sideways to the Sun sweeps gloriously, but never loses its poignant impulse. Check it out.

Fans of that old chestnut I'll Be Waiting will hear an orchestra play along with the tune as if they had been working with Horslips from the time it was first performed. Guitarist Johnny Fean efforlessly peels off yet another one of his deathlessly soaring solos and a blistering genius solo too on Charolais. Dearg Doom, well what can you do with Dearg Doom that's going to better it? During Jim Lockhart's tin whistle solo, the string section arrangements work an interesting counterpoint - it's about real musical imagination and verve.

Away from the rockier terrain, the harp lends a sunny dimension to concertina-led pieces like Drive The Cold Winter Away and Maeve's Court, whose stately formalism reminds you yet again how good and perhaps neglected this tune is.

"Youre always a pleasure, thank you Belfast, " says Charlie O'Connor, towards the close of the gig. Charlie is the man who threw his mandolin - or was it his fiddle?- into the Ulster Hall audience in 1980 when the band decided to take a couple of decades out. Was the lucky recipient there that night last year, one muses, as a band we thought had gone forever surprise us all over again?

Paddy Kehoe