The Beatles (album) stereo only. In the UK, the following album, "Yellow Submarine", was the last to be shipped in mono. The mono version of "The Beatles" was made available worldwide on 9 September 2009, as part of "The Beatles in Mono" CD boxed set. A reissue of the original mono LP was released worldwide in September 2014. The album's sleeve was designed by pop artist Richard Hamilton, in collaboration with McCartney. Hamilton's design was in stark contrast to Peter Blake's vivid cover art for "Sgt. Pepper's Lonely Hearts Club Band", and consisted of a plain white sleeve. The band's name, in Helvetica,
Sgt. Pepper's Lonely Hearts Club Band peers", he continues, "what was revolutionary was the sonic carpet that enveloped the ears and sent the listener spinning into other realms." Stephen Thomas Erlewine of AllMusic considers the album to be a refinement of "Revolver"s "previously unheard-of level of sophistication and fearless experimentation" and a work that combines a wide range of musical styles yet "Not once does the diversity seem forced". He concludes: "After "Sgt. Pepper", there were no rules to follow – rock and pop bands could try anything, for better or worse." In 1987, Anthony DeCurtis of "Rolling Stone" described "Sgt. Pepper" as the album that