Krause later said that, with "No Time or Space", Harrison recorded the studio demonstration without his knowledge and that it incorporated ideas he was due to include on his forthcoming album with Paul Beaver.

The front cover shows Krause operating the Moog console, while the back depicts Derek Taylor's office at Apple and the pressures afflicting the company at the time.

[4][5] These instruments included Hammond organ on some of his songs with the Beatles, and Mellotron[6][7] on several of the Western selections on his debut solo album, the Wonderwall Music film soundtrack.

[8][9] Described by producer George Martin as the most dedicated of the Beatles in finding and creating new sounds for the band's studio recordings,[10] Harrison became intrigued by the potential of the Moog synthesizer while in Los Angeles in late 1968.

[37] At Harrison's request, Krause first persuaded customs officers at Heathrow Airport that the system was a musical instrument and to accept a minimal tariff to release the equipment.

[41][nb 3] The notes accompanying the track listing on the LP sleeve were taken from a Zapple press release written by Richard DiLello,[44] who served in the position of "house hippy" at Apple.

[44] According to Beatles historian Bruce Spizer, the vivid colours and childlike quality of the artwork "add a feeling of lightness" to the austere sounds found on the album.

[47] Harrison's son Dhani says that the two sleeve images were part of a single large painting, which he discussed with his father after discovering it in the family home, Friar Park, in the 1990s.

Harrison appears as a small blue smiling face below this, "making the tea", while the green shape along the bottom of the image represents Jostick,[48] one of his and Pattie Boyd's Siamese cats.

[57] Author Mark Brend describes the cover art as "a twist on the convention of making the instrument itself a focus", since the four Moog modules appear to be grouped together behind the synthesizer player as if they are his backing musicians.

[64][nb 5] Electronic Sound was sullied further after Krause wrote to Rolling Stone magazine complaining of Harrison's appropriation of his demonstration piece and saying that he was "frankly hurt and a bit disillusioned by the whole thing".

[74] Rather than include the planned 1000-word liner note essay in the CD booklet for his album, he supplied his own text, reading simply: "It could be called avant-garde, but a more apt description would be (in the words of my old friend Alvin), 'Avant Garde Clue'!

He found little meaning in the combination of mechanical sounds on "No Time or Space" and said that "Under the Mersey Wall" was more musical, with a semblance of form revealing itself after an opening that he likened to "someone learning an instrument".

[78] Melody Maker compared Electronic Sound favourably with Wendy Carlos's Moog album Switched-On Bach, which became a surprise commercial hit after entering the Billboard Top LPs chart in March.

"[58] In his joint review of Electronic Sound and Life with the Lions, Ed Ward of Rolling Stone dismissed the Lennons' album as "utter bullshit"[21] and said that Harrison had "done quite well learning his way around his new Moog Synthesizer ... but he's still got a way to go".

He says that Harrison's fascination with the Moog typified the interest the new instrument received from top rock musicians at the time, and he adds: "Luckily for us he decided to release it (with a great cover painting by a small child) … While my Synth gently beeps.

"[91] Writing for The New York Observer, Ron Hart considers it to be one of Harrison's unjustly overlooked works and he says that while it was tainted by the controversy with Krause, the project stands as an "oddly visionary testament to the Zapple label and its unsung promise to bring the avant-garde to the pop crowd".

[94][nb 7] Scott Elingburg of PopMatters welcomed its Apple Years reissue and described the album as the artist's "most 'experimental' work" and, like the remastered Wonderwall Music, "raw and gorgeous, alive and capable of sparking ingenuity".

He said that while Harrison was not a synthesizer innovator in the mould of Brian Eno or Jeff Lynne, "the intention behind Electronic Sound is one of exploration and discovery, an artist limbering up his musical mind to discover how far the boundaries of modern instrumentation could take him.

[14] Once installed at EMI Studios in August 1969, where Mike Vickers of the band Manfred Mann assisted in programming the system,[98] Harrison's Moog proved to be an important addition to the Beatles' final recording project.

The authors write that the perception in the recording industry during the late 1960s was typically that, because of the highly technical aspect of the Moog modular system, these pioneers were simply engineers rather than artists or musicians.

[108] Malcolm Cecil, who went on to become a leading synthesizer proponent as the co-creator of TONTO,[109][110] recalls that when he first encountered a Moog 3P, his immediate thought was: "Geez, this is the [instrument] that George Harrison made that record on.

[112] In his introduction to the 2014 CD booklet, he recalls discovering a rare copy of the LP in a Tokyo record shop in the 1990s and says that the sleeve "now hangs on the wall of my studio, just next to my own Moog modular, beaming inspiration straight to my brain".

[115][116] The author said he relished the record for providing "all the scant moments of raging Moog-osity I always craved more of as a teenage Emerson, Lake & Palmer fanatic", and described its two tracks as "aural rollercoaster rides, featuring alarming and unusual zapping twists over an assortment of tone colours, pitch-controlled hi-jinks and outright experimentalism in the most extreme album Harrison would ever produce".