Superunknown is the fourth studio album by American rock band Soundgarden, released on March 8, 1994, through A&M Records. Produced by Michael Beinhorn and the band themselves, Soundgarden began work on the album after touring in support of their previous album, Badmotorfinger (1991). Superunknown retained the heaviness of the band's earlier releases while displaying a more diverse range of influences.

Superunknown was a critical and commercial success and became the band's breakthrough album. It debuted at number one on the Billboard 200, selling 310,000 copies in its opening week. The album also topped the Australian, Canadian, and New Zealand charts. Five singles were released from the album: "The Day I Tried to Live", "My Wave", "Fell on Black Days", "Spoonman", and "Black Hole Sun", the latter two of which won Grammy Awards and helped Soundgarden reach mainstream popularity. At the 37th Grammy Awards, the album was nominated for the Grammy Award for Best Rock Album. It has been certified 6× Platinum by the Recording Industry Association of America (RIAA) in the United States. Superunknown has been listed by several publications as one of the best albums of the 1990s and a quintessential grunge album. In April 2019, it was ranked No. 9 on Rolling Stones "50 Greatest Grunge Albums" list.

Recording Soundgarden began work on its next album about two months after finishing its stint on the 1992 Lollapalooza tour. The individual band members wrote material on their own before bringing in demos to which the other members would contribute. Frontman Chris Cornell noted that the band allowed each other more artistic freedom than on previous records. Guitarist Kim Thayil observed that even though the band spent as much time writing and arranging as it had on previous albums, it spent a lot more time working on recording the songs. After two albums with producer Terry Date, the band decided to seek another collaborator. Thayil said, "We just thought we'd go for a change." Eventually they settled on producer Michael Beinhorn, who "didn't have his own trademark sound which he was trying to tack on to Soundgarden" and had ideas the band approved.

The album's recording sessions took place from July 1993 to September 1993 at Bad Animals Studio in Seattle, Washington, as according to Cornell "there was never a decent studio in Seattle and now there's one with a Neve console, so it seemed obvious to use it". Bad Animals' resident engineer Adam Kasper, who went on to produce Soundgarden's following albums, assisted Beinhorn on the recording process. Soundgarden took the approach of recording one song at a time. The drum and bass parts were recorded first for each song, and then Cornell and Thayil would lay down their parts over top. Cornell said that getting to know Beinhorn contributed to the length of time Soundgarden spent working on the album. The band spent time experimenting with different drum and guitar sounds, and utilized production techniques such as layering to achieve an expansive production sound. Cornell noted, "Michael Beinhorn was so into sounds. He was so, almost, anal about it, that it took the piss out of us a lot of the time... By the time you get the sounds that you want to record the song, you're sick and tired of playing it." Beinhorn tried to add many of his preferred musicians to mold the band's sound, in what Billboard described as "weaning the band from brute force, giving it the impetus to invest in a more subtle power." For instance, prior to tracking the vocals for "Black Hole Sun", Beinhorn had Cornell listen to Frank Sinatra.

Superunknown features 15 songs and a runtime of approximately 70 minutes because, according to Cornell, the band members "didn't really want to argue over what should be cut." Soundgarden paused the recording sessions to open for Neil Young on a ten-day United States tour. Afterward, the band hired Brendan O'Brien to mix the album because Beinhorn felt they needed "a fresh pair of ears"; O'Brien was recommended by Pearl Jam guitarist Stone Gossard. Thayil called the mixing process "very painless", and bassist Ben Shepherd remembered it as "the fastest part of the record."

Behind-the-scenes footage of the band tracking and mixing "Kickstand" was featured in the "Sound" episode of Bill Nye the Science Guy.

Outtakes Although the album's singles featured quite a few B-sides, only "Exit Stonehenge" (from the "Spoonman" single) was sourced from the Superunknown recording sessions in 1993. "Cold Bitch" (also from "Spoonman") was recorded during the Badmotorfinger recording sessions in 1991, "Kyle Petty, Son of Richard" and "Motorcycle Loop" (both from the "Fell on Black Days" single) were recorded by Stuart Hallerman at Avast Studios in Seattle in 1994. "Kyle Petty, Son of Richard" was later featured on the 1996 Home Alive compilation. "Tighter & Tighter", "No Attention", and "An Unkind", all of which later appeared on the band's 1996 album, Down on the Upside, were attempted during the Superunknown recording sessions."Hard Stuff, Soundgarden in the Studio". Livewire. 1993.Zogbi, Marina. "Upshot on 'The Upside' from Kim Thayil". Metal Edge. August 1996. Cameron said that the band wasn't pleased with the recording of "No Attention" that came out of the sessions.Rule, Greg. "Matt Cameron of Soundgarden: Balance of Power & Grace". Drum!. September 1996. An instrumental entitled "Ruff Riff-Raff" and a light-hearted song called "Bing Bing Goes to Church" were recorded at album rehearsals but were presumably not recorded during the Superunknown recording sessions. Both were released in 2014 on the 20th anniversary Super Deluxe edition.

Composition The songs on Superunknown retain the grunge and alternative metal sound of the band's previous works, while embracing alternative rock, hard rock, heavy metal, and psychedelic rock. Steve Huey of AllMusic said the band's "earlier punk influences are rarely detectable, replaced by surprisingly effective appropriations of pop and psychedelia." Cornell labeled the album as more "challenging" and "versatile" than the band's previous releases. The songs on the album are more experimental and diverse than the band's previous recordings, with some songs having a Middle-Eastern or Indian flavor (for example "Half", sung by Shepherd). Some songs also show a Beatles influence, such as "Head Down" and "Black Hole Sun". In a 1994 interview with Guitar World, Thayil explained, "We looked deep down inside the very core of our souls and there was a little Ringo sitting there. Oh sure, we like telling people it's John Lennon or George Harrison; but when you really look deep inside of Soundgarden, there's a little Ringo wanting to get out." Drummer Matt Cameron said that the experimentation on the album was "just a matter of refinement." According to The A.V. Club, the album "both redefined and transcended grunge". Michael Beinhorn stated that to achieve the intensity of Superunknown, he sought influence from European electronic music, such as the British Aphex Twin and the Dutch genre of Gabber, described by him as "some of the rawest music made".

Soundgarden used alternate tunings - and tuned their guitars a quarter step down - and odd time signatures across several tracks. "Spoonman", "Black Hole Sun", "Let Me Drown", and "Kickstand" are performed in drop D tuning, whereas "Fell on Black Days" uses standard tuning. Other songs employ more unorthodox tunings: "Superunknown" and "Fresh Tendrils" are tuned to DGDGBe, and "Like Suicide" utilizes a similar DGDGBC arrangement. "My Wave" and "The Day I Tried to Live" both use EEBBBe; "Mailman" and "Limo Wreck" employ CGDGBe; "Head Down" and "Half" utilize CGCGGe; and "4th of July" features CFCGBe tuning. The band's use of odd meters was equally varied: "Fell on Black Days" is written in 6/4, "Limo Wreck" is in 15/8, "My Wave" alternates between 5/4 and 4/4, "The Day I Tried to Live" alternates between 7/8 and 4/4, and "Spoonman" alternates between 7/4 and 4/4 sections. Thayil noted that Soundgarden rarely considered a song's time signature until after it was completely written, calling the use of odd meters "a total accident."

Lyrically, the album is dark and mysterious, exploring themes of substance abuse, suicide, and depression, alongside running motifs of revenge, annihilation, seclusion, fear, loss, death, and discovery. Cornell was heavily inspired by the writings of Sylvia Plath during the writing sessions. Commenting on the album's lyrics, Thayil said that "a lot of Superunknown seems to me to be about life, not death. Maybe not affirming it, but rejoicing—like the Druids [put it]: 'Life is good, but death's gonna be even better!" Cameron said that the lyrics on the album are "a big fuck-you to the world, a plea to 'leave us alone. Cornell stated that "Let Me Drown" is about "crawling back to the womb to die", "Fell on Black Days" is about realizing "you're unhappy in the extreme", "Black Hole Sun" is about a "surreal dreamscape", "Limo Wreck" is a "shame-on-decadence song", "The Day I Tried to Live" is about "trying to step out of being patterned and closed off and reclusive", and "4th of July" is about using LSD. Cornell talked about "Mailman" at a concert saying, "This next one is about killing your boss. It's about coming to work early one morning cause you have a special agenda and you're going to shoot him in the fucking head." Conversely, "Like Suicide" was literal, written by Cornell after a bird flew into a window of his house. He found the severely injured animal and killed it, hitting it with a brick to end its suffering.

The video clip of the song "Spoonman" is notable for featuring a performance by Artis the Spoonman, a street entertainer in Seattle. The title of the song is credited to bassist Jeff Ament of Pearl Jam. While on the set of the movie Singles, Ament produced a list of song titles for the fictional band featured in the movie. Cornell took it as a challenge to write songs for the film using those titles, and "Spoonman" was one of them. An acoustic demo version of the song appears in the movie. Cornell said that the song is about "the paradox of who [Artis] is and what people perceive him as".

Packaging The album's cover art (known as the 'Screaming Elf') is a distorted photograph of the band members, photographed by Kevin Westenberg, above a black and white upside-down burning forest. Concerning the artwork, Cornell said, "Superunknown relates to birth in a way ... Being born or even dying—getting flushed into something that you know nothing about. The hardest thing is to nail down a visual image to put on a title like that. The first thing we thought of was a forest in grey or black. Soundgarden has always been associated with images of flowers and lush colors and this was the opposite. It still seemed organic but it was very dark and cold ... I was into those stories as a kid where forests were full of evil and scary things as opposed to being happy gardens that you go camping in." In a 1994 Pulse! magazine interview, Cornell said that the inspiration for the album's title came from his misreading of a video entitled Superclown. He added, "I thought it was a cool title. I'd never heard it before, never saw it before, and it inspired me." The album also saw a limited release on 12" colored vinyl (blue, orange, and clear), as a double-LP in a gatefold sleeve.

On May 25, 2017, photographer Kevin Westenberg revealed the full photo from the cover for the first time on his Instagram account.

Critical reception