When My Bloody Valentine released Loveless on Nov. 4, 1991, it became an album that defined a genre, laid much of the groundwork for the alternative movement that dominated the rest of the decade and was hailed as one of the most important albums of the '90s. But for all its praise and influence, the beauty of this record is in the way it travels simultaneously to opposite ends of the musical spectrum and combines its two final extremes: pop music and drone.

Humans have been listening to drone -- or, at least, hearing it -- as long as we've had ears. For millennia and perhaps longer, we've found various ways to produce our own drones and we have employed them in various services. Drones accompany religious services, meditation and spiritual release. Traditional music from Scotland to India to Australia is rooted in deep drones, sometimes shifting from pitch to pitch, glacially, sometimes sounding the same tone invariably and unendingly, but always with the effect of dissociating listeners and participants from their earthly bodies.

Drones are non-emotional and, in the Western sense, non-musical. Unlike a Bach concerto or a Beethoven symphony or a Wagner opera, a drone doesn't have an agenda. Western music pieces were historically meant to be complete artifices, like buildings or novels. They cast out nature; they are part of an enlightened drive toward orderliness. Drones, on the other hand, seek to emulate nature and to join it. Narrative arcs exist in novels but rarely in real life. Real life, moving forward, brings bumps and turns along an unpredictable path. The drone is rhythmless and melody-less with no clear beginning or end. There's no structure. It emulates the movement of this river of life.

As composers in the mid-20th century worked to dismantle the central concepts of rhythm and structure that had for so long underpinned Western music, they naturally looked to employ drones. In beatnik New York during 1964, composer La Monte Young founded the Theatre of Eternal Music and he brought on a young viola player named John Cale, whose interest in the possibilities of drone matched his own. Cale, in turn, struck up an unlikely friendship with a street poet named Lou Reed whose manic obsession with pop music rivaled Cale's own love of drone. In a way, Cale's association with Reed was more avant garde than Young's eternal music; if drone is anti-Bach and anti-Beethoven, it's surely also anti-pop. Perhaps Cale and Reed's finest achievement together was the recording of "Heroin" in May, 1966 in Los Angeles, during the sessions for the Velvet Underground's first album. Reed narrated shooting up. "I'm gonna try to nullify my life," he declared. Cale accompanied with a pure viola drone -- enveloping Reed's moment, canceling out the outside world, meaningfully obscuring him as the drugs would also do, negating everything but the spike and the veins.

Cale and Reed lived together in the brain of My Bloody Valentine frontman Kevin Shields  – even if he didn't know it. He formed the band in Dublin in 1983 and spent five years working with a shifting cast of band members and striking out at various fashionable sounds. Shields was enamored with pop and felt that it held a deeper potential for listeners than it often got credit for -- that it could be interpreted like a poem and lived inside.

Steve Double

Experiments coalesced over the years -- from an early tendency to record songs on a tape deck and play over the top of them live to the additions of pitch-bending modulators, the tremolo bar and heaps of sheer volume. Their 1988 album Isn't Anything is a near-perfect synthesis of these elements.

But Shields was a perfectionist, and he spent the next two years in the studio leading the band (singer-guitarist Bilinda Butcher, bassist Debbie Googe and co-founder and drummer Colm Ó Cíosóig) through the arduous recording of their follow-up. Two years later, the band delivered Loveless.

"When you hear something and you don’t know where it’s beginning or ending, suddenly your imagination is fifty percent of what’s happening,” Shields told Arthur magazine in 2003. This is the drone and it is the essence of Loveless. The songs on Loveless are fully formed melodically -- evident in the tidal riffs of "Only Shallow" and the instantly recognizable and almost groovy "When You Sleep." There are the moments that barely seem to break through the roar of guitar, though just barely. For the most part, everything is buried, drenched in it. The way drones had invited past listeners to explore the timbre of bagpipes, tambura and human voice, Loveless unfolds the worlds contained within guitars, effects pedals and amplifiers. Chord changes are barely perceptible. Words are barely enunciated and barely formed.

The effect of combining melody and rhythm so intimately with the sound of the drone is an imitation of life in a way -- the lull of routine, broken up suddenly with pockets of meaning. Like most pop albums, Loveless concerns love. But most pop albums are like edited versions of our love lives with the lulls subtracted: it's all euphoric high and desolate low. Loveless immerses you in the flow and only occasionally whip you out of it. This happens often, as when the thick, pulsing drone of "To Here Knows When" descends into a quiet, burbling guitar sketch, then gives way to "When You Sleep," perhaps the album's most lucid moment, and the only one in which Shields' voice is clearly discerned.

"Sometimes" is a song where listeners really do 50 percent of the work -- a pretty song with a pretty melody that's simply covered over with guitar. It's lyrically tumultuous, even if there's little meaning to be gleaned from it; the only solution Shields offers: "Turn my head / Into sound" as his mantra. The poppiest moments on "Come in Alone" and "Soon" (which melodically and rhythmically predict so much of the alternative rock of the '90s) are ultimately elusive. If the perfect pop record is like a novel, Loveless is a novel with the last 10 pages ripped out.

Shields said in 2003, "Around 1990 it seemed like music could just do anything and then it seemed to close down dramatically again." Even if you don't agree, you have to admit that rock music never truly lived up to Loveless. Bands like Smashing Pumpkins and Garbage imitated it successfully; Boards of Canada pushed it into wholly electronic territory. More often than not, the sounds these bands used were simple adornments, flourishes that made the songs sweeter to the ear but never threatening to destroy the songs. Like the Velvet Underground a quarter-century before them, My Bloody Valentine created a sound many bands would approach but none would quite manage to capture.

Shields himself couldn't even manage to follow up Loveless until 2013. It was as if he'd made a record that was just out of reach even of himself – though, when he did, it was a thing of beauty. The legacy of Loveless is the way it always stays just out of reach, keeping its melodies and turning points hidden and indiscernible, the way such moments really are. This is its true accomplishment -- it's the marriage of the pop song and the drone; the artifice and anti-music.

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