ECHO & The Bunnymen’s Ocean Rain is “the greatest album ever made”. Who says so? Step forward the never-shy-in-stepping-forward Ian McCulloch, lippy lead singer of the psychedelic Liverpudlians, and what’s more he said it before its release in 1984.

But rather than dismissing it as rock’s great statement of braggadocio ever made, hear him out on the eve of Ian and guitarist Will Sergeant and their latest Bunnymen line-up setting out on a six-date tour tomorrow that will revisit the album in its majestic entirety. Thursday’s gig in York at the Grand Opera House has long sold out, adding further grist to his mill.

“At the time that was what I was like,” says Ian, who was 25. “Look, The Killing Moon was the best song ever written, and if you say something like ‘it’s the greatest album ever made’ to the record company boss, as soon as he heard it, he must have made a note of it and Rob Dickens from Warners then put it in the press release. Rob probably now thinks he made the original comment!”

Certainly, Ocean Rain, their fourth studio set and their most ambitiously grandiose, proved to be the greatest album the Bunnymen ever made, spawning the hits The Killing Moon, Silver and Seven Seas, as well as live favourite Ocean Rain.

“I never understood why there was such a fuss about what Ian said,” says Will. “I’d say it was just self-belief. We were trying to change things a bit musically, move it on after punk had come and been such a blow to the head that it couldn’t go on and became too samey very quickly apart from Wire and Pere Ubu.”

Not everyone shared Ian’s opinion on Ocean Rain’s superiority to all around it. “When it came out, the NME said it sounded like the Moody Blues... but I like the Moody Blues. See Saw, I like that. I still play that when I DJ,” says Will.

“I was totally into the psychedelia. Punk had been the inspiration for the fact that you didn’t have to be a bloke from Yes to play music, but I’d have loved to have had a cape – though I knew I wouldn’t be able to play like the bloke from Yes as I didn’t have the patience. It was like, ‘Get on with it’.

“But I’ve always liked stuff that takes your mind somewhere else, takes you on a journey, starting with I Am The Walrus when I was a kid and seeing The Magical Mystery Tour on the telly. And when we used to go to Eric’s [club] in Liverpool, though they played mostly punk, they also did Nuggets stuff, the Chocolate Watch Band and the 13th Floor Elevators.”

There was no calculation to the Bunnymen’s explorations that peaked with Ocean Rain.

“We never thought about it that much; we were just into Scott Walker, playing his music in the van, and Jacques Brel because when we played in Brussels we got introduced to him,” says Will. “We never had a plan except not to do s*** songs.

“But they were different times because record companies supported you and didn’t drop you after one failure.”

Rather than being ambitious, says Will, the band’s drive was to experiment and Warners backed the Bunnymen’s every whim, sending them out to Paris for three weeks.

“There we were diving around Paris, like two Parisian fools,” he recalls. “We purposely chose French influences… and the budget kept rising, because we got a French arranger to come in. “But Mac took an instant dislike to him, so we got our mate Adam Peters, from the Royal College of Music, to do the strings instead.”

On the back of devoting a tour to reviving their debut album, Crocodiles, the Bunnymen first revisited Ocean Rain, strings and all, two years ago at the Royal Albert Hall, London, Radio City Music Hall in New York and a homecoming gig at Liverpool Echo Arena to mark their 30th anniversary. This autumn, they do so again, accompanied once more by string players.

“The Albert Hall, Radio City and Liverpool were my three favourite ever shows, but I wanted to just give it some time before dong it again, going back to the compilation set first,” says Ian. “Now can’t wait to do it.”

He loves the Ocean Rain songs as much as ever.

“They just sounded different from anything we’d done as we wrote them acoustically around my house. That was the template that was different from before. It was steeped in European classical songwriting,” he says.

On Thursday, those songs will be played in York for the first time.

“What’s more frightening than the album being 27 years old is that we last played York in 1979 when we played with a local band called Cyanide…” says Ian.

Will can still remember the occasion.

“They were a skinhead band and we thought they were going to batter us... so we let them go on last!”

• Echo & The Bunnymen play Ocean Rain at the Grand Opera House, York, on Thursday at 7.30pm; sold out.