By the spring of 1994, grunge was reaching its zenith and some wondered just how much more the Seattle-centric genre had left in the tank. Everywhere you looked, the rapidly acquired fame and fortune the scene had been enjoying was starting to take its toll, as rockers used their newfound cash to sink deeper and deeper into downward spirals of depression and drug addiction. By April of that year, Nirvana’s Kurt Cobain would be dead, allegedly from a self-inflicted shotgun blast.

Soundgarden, however, were just getting started. A pioneering band of the genre during the '80s and one of Seattle's “Big Four” (along with Nirvana, Pearl Jam and Alice in Chains), the quartet hadn’t dropped a full-length since 1991’s essential Badmotorfinger. But the game had substantially changed since then. No longer was it enough to just wow listeners with guitarist Kim Thayil’s droning low-tuned riffs or singer Chris Cornell’s trademark howl; the band had been there, done that… and had already done it very well. It was time to push further and that’s exactly what they did.

Writing for Superunknown began in 1992 after the band wrapped their stint on Lollapalooza. Each member developed ideas on his own, then shared demos with the rest of the band during what was the most open and collaborative process they’d experienced to that point. Armed with new material, they chose Michael Bienhorn (Red Hot Chili Peppers, Soul Asylum) to produce after they recorded their first two records with legendary studio whiz Terry Date. The impact was immediate: From the start, Bienhorn gave Soundgarden the space to experiment and redefine their sound, which they took full advantage of.

Led by Bienhorn, the group buckled down to record from July to September 1993 at Bad Animals Studio in Seattle, which boasted one of the legendary Neve consoles among its gear. Soundgarden methodically recorded each song one at a time to completion, while experimenting with layered guitar and drum sounds to create a broader, more massive sonic space. The band took a 10-day break in the middle of the sessions to open for Neil Young before completing the album. They hired Brendan O’Brien (Pearl Jam, Stone Temple Pilots) to mix the nearly finished product.

Even if the process seemed maddeningly slow at times, it was beneficial. The resulting batch of songs were arguably Soundgarden’s finest collection ever, spawning five well-received singles: “Spoonman,” “The Day I Tried To Live,” “Black Hole Sun,” “My Wave” and “Fell on Black Days,” amid 15 total tracks and 70 minutes of consistently intense music. The album went on to become not just Soundgarden’s breakthrough record, but also their definitive work.

Part of that stemmed from the depth and diversity of the album. Superunknown embraced the hard-charging punk and metal that drove the band’s past creations, but combined those harder sensibilities with a broadening sonic palette that included Beatles-styled pop, lush psychedelia and exotic Middle Eastern and Indian tones, as well as a litany of odd tunings and time signatures. Bienhorn assisted in that process, to be sure, even having Cornell listen to Frank Sinatra prior to recording the croon-worthy hit “Black Hole Sun.”

Cornell also pushed himself to pen some hauntingly tortured lyrics. Although many of his lyrical meanings remain mysterious even today, it was clear the themes on the album include vengeance, death, isolation, terror, loss and discovery, all wrapped in an overall concept of an existential trip into the void through either birth or death (the proverbial “super unknown”). One of the only tracks with a literal commentary was “Like Suicide,” which Cornell wrote about a bird that crashed into his window, which he then dispatched with a brick in order to end its suffering.

Critics almost immediately recognized the genius of the album. Rolling Stone said, “At its best, Superunknown offers a more harrowing depiction of alienation and despair than anything on [Nirvana’s] In Utero.” Entertainment Weekly agreed, calling it a “hard-rock milestone – a boiling vat of volcanic power, record-making smarts and ’90s anomie and anxiety that sets a new standard for anything called metal.” Even the Village Voice’s Robert Christgau (who was never a Soundgarden fan) conceded the album that was “easily the best – most galvanizing, kinetic, sensational, catchy – Zep rip in history.”

Fans also responded, with CDs flying off shelves everywhere. Superunknown debuted at No. 1 on the Billboard 200, selling 310,000 copies in its opening week. The album has been certified five times platinum by the RIAA in the U.S., three times platinum in Canada and gold in the U.K., Sweden and the Netherlands. It has sold roughly 9 million copies worldwide and remains Soundgarden’s most successful album. Further, “Spoonman” and “Black Hole Sun” both won Grammys, while the album was nominated for a Grammy in 1995 for Best Rock Album.

In 2014, a 20th-anniversary reissue of Superunknown was released in two deluxe versions: a double-CD featuring the remastered album and a second disc with demos, rehearsals, B-sides and more; and a super deluxe version four-CD package that also includes additional demos, rehearsals and B-sides in a hardbound book package.

However, Soundgarden’s (original) lifespan didn’t last too much longer after Superunknown’s release. The band saw considerable success with 1996’s Down on the Upside, but then disbanded in 1997. They didn't record together again until reemerging in 2012 with King Animal.

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