on March 8, 1994, Superunknown became the band's breakthrough album, debuting at number one on the Billboard 200 album chart and being driven by the singles "Spoonman", "The Day I Tried to Live", "Black Hole Sun", "My Wave", and "Fell on Black Days". The songs on Superunknown captured the creativity and heaviness of the band's earlier works, while showcasing the group's newly evolving style. Lyrically, the album was quite dark and mysterious, and it is often interpreted to be dealing with substance abuse, suicide, and depression. At the time, Sylvia Plath inspired Cornell's writing. The album was also more experimental than previous releases, with some songs incorporating Middle-Eastern or Indian music. J. D. Considine of Rolling Stone said Superunknown "demonstrates far greater range than many bands manage in an entire career". He also stated, "At its best, Superunknown offers a more harrowing depiction of alienation and despair than anything on [Nirvana's final studio album] In Utero." The music video for "Black Hole Sun" became a hit on MTV, and received the award for Best Metal/Hard Rock Video at the 1994 MTV Video Music Awards, and in 1995 the Clio Award for Alternative Music Video. Soundgarden won two Grammy Awards in 1995—"Black Hole Sun" received the award for Best Hard Rock Performance and "Spoonman" received the award for Best Metal Performance. The album was nominated for a Grammy Award for Best Rock Album in 1995. Superunknown has been certified six times Platinum in the United States and remains Soundgarden's most successful album. The band began touring in January 1994 in Oceania and Japan, areas where the record came out early and where the band had never toured before. This round of touring ended in February 1994. In March 1994 the band moved on to Europe. They began a theater tour of the United States, first with a stop on May 27, 1994 at the PNE Forum in Vancouver, with the opening acts Tad and Eleven. In late 1994, after touring in support of Superunknown, doctors discovered that Cornell had severely strained his vocal cords, and Soundgarden canceled several shows to avoid causing any permanent damage. Cornell said, "I think we kinda overdid it! We were playing five or six nights a week and my voice pretty much took a beating. Towards the end of the American tour I felt like I could still kinda sing, but I wasn't really giving the