Regarded as one of the most ground-breaking, important and influential albums of all time, Sgt Pepper has divided critics and even Beatles fans over the years – Keith Richards recently called it “a mishmash of rubbish.” Others. meanwhile, have pointed to its overly self-conscious “artiness” and accused it of being a step too far from the roots of rock.

But half-a-century from its release in the Summer of Love, it still resonates powerfully. Like it or not, the innovative use of technology – with multi-layered sound montages and non-rock instrumentation – was a sonic revolution (the influence of LSD, of course, also permeates the album).This six-disc super-deluxe version is surely the last word on Sgt Pepper, containing as it does no less than 65 tracks. The package boasts the original album in both remixed stereo and mono configurations, along with multiple different takes of the songs, including overdubs, instrumental passages and studio chatter.

Of course, some of the tunes are simply jaw-dropping: the heartbreaking ‘She’s Leaving Home’, the haunting ‘A Day In The Life’ and the trippy ‘Lucy In The Sky With Diamonds’ are worth the price of admission alone.

Elsewhere, lesser known tracks such as Paul McCartney’s intricately structured ‘Fixing A Hole’ and the quirky ‘Lovely Rita Meter Maid’ hold up exceptionally well. For many Fab Four aficionados, the real icing on the cake will be the inclusion of ‘Strawberry Fields Forever’ and ‘Penny Lane’, both songs recorded during the Pepper sessions, but released as a standalone double-A side single.

The former is arguably – and there are always arguments – the Beatles’ greatest recorded achievement – a true, multi-layered psychedelic odyssey. ‘Penny Lane’, meanwhile, is a charmingly nostalgic pop classic. There are multiple takes of both songs included, with the early versions of ‘Strawberry…’ demonstrating the extraordinary development of the tune, from its simple demo incarnation into one of the most famous pieces of music in the history of rock and pop.

Out June 1 //Colm O'Hare