The Beatles Abbey Road was/is a miracle. Personal, financial, and musical battles had shattered their ability to work together. Geoff Emerick (their long-time chief recording engineer) stated in his book Here, There and Everywhere regarding the 1968 sessions for The Beatles "for weeks I had been incensed about what had been going on, with the horrible, unsettled atmosphere, the constant bickering." He was so distraught that he demanded to be reassigned by EMI, leaving the project in midstream. By all accounts the Get Back sessions the following January were even worse. George Harrison temporarily quit the band, the music degenerated into long jam sessions, John Lennon told George Martin that these session were no place for his slick production work.
With the Get Back project on the shelf, the realization set in that the end was near. McCartney and George Martin decided to attempt a recording done the way they used to do it, with Martin guiding the production, and the Beatles once again playing together as a cohesive band. Sensing that it might be their last shot, the other three agreed to the terms, and Geoff Emerick was persuaded to return.
Various rock critics have referred to the mini-suite on the second side as a pop symphony. But if one must attribute classical forms to this work, I think a more apt description is tone poem. From the Wikipedia page for Tone Poem: combined or compressed multiple movements into a single principal section. Most folks consider the suite to start with a song which in itself is a multi-part composition - Paul's amazing You Never Give Me Your Money. For me the entire LP side constitutes the tone poem. The lyrics from the chorus of Here Comes the Sun return in Sun King, as do the transplendent multi-layered vocal harmonies from Because. Outside of the Beach Boys, 11th chords have never been used so effectively in a pop framework.
From George's most sunny and possibly finest melody until Paul's little throwaway ode to the Queen, everything that made the Beatles a force of nature can be found here. Frankly I prefer to listen to it non-stop from start to finish. Even John's two little character studies Mean Mr. Mustard and Polythene Pan - which taken on their own are a bit slight (especially the former) - in the context of the suite, and glued together with Beatle's magic, are an essential portion of the experience.
Nicholas Schaffner, in his fine book The Beatles Forever said "The album as it stands shows four musicians, all at the height of their powers but each tuned into very different wavelengths, making one final effort to work together creatively and efficiently. McCartney, who hasn't yet given up on Art, attempts to weld a glittering scrapheap of fragments into an ambitious song cycle. Between them, the sparks fly." Indeed.
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