Dinosaur Jr. is an American alternative rock band formed in Amherst, Massachusetts in 1984. Originally called Dinosaur, prior to legal issues that forced the group to change their name, the band disbanded in 1997 until reuniting in 2005. Guitarist J Mascis, bassist Lou Barlow, and drummer Murph were the band's founding and current members; Mascis has been the group's sole continuous member.
Their distinct guitar sound, characterized by high gain, extensive use of feedback and distortion, and frontman J Mascis's melodic guitar solos, was highly influential in the alternative rock movement of the 1990s.
Mascis and Barlow had previously played together in a hardcore punk band called Deep Wound, formed in 1982 while the pair were attending high school in western Massachusetts. After high school, they began exploring slower yet still aggressive music such as Black Sabbath, The Replacements, and Neil Young. Mascis' college friend Gerard Cosloy introduced him to bands like Dream Syndicate, which Mascis in turn showed to Barlow. Barlow explained, "We loved speed metal...and we loved wimpy-jangly stuff".
Deep Wound broke up in mid-1984. Cosloy had dropped out of the University of Massachusetts Amherst to focus on running his independent record label, Homestead Records, and promised Mascis that if he were to make a record Homestead would release it. Mascis wrote a number of songs by himself and showed them to Barlow, to whom he offered the bassist position. While Barlow had played guitar in Deep Wound, he accepted as he was impressed by the material Mascis was creating. Barlow said the songs "were fucking brilliant...They were so far beyond. I was still into two-chord songs and basic stuff like 'I'm so sad.' While I was really into my own little tragedy, J was operating in this whole other panorama." Mascis enlisted vocalist Charlie Nakajima, also formerly of Deep Wound, and drummer Emmett Patrick Murphy, otherwise known as Murph, to complete the band. Mascis explained the concept behind the group as "ear-bleeding country."
The band was initially named Mogo, and played their first show on University of Massachusetts Amherst campus in the first week of September 1984. Nakajima went into an anti-cop rant during the performance, and Mascis was so appalled by his behavior at the show that he disbanded the group the next day. A few days later Mascis called Barlow and Murph to form a new band without telling Nakajima; "I was kind of too wimpy to kick him out, exactly," Mascis later admitted, and explained, "Communicating with people has been a constant problem in the band." The trio named themselves Dinosaur, and Mascis and Barlow took over lead vocal duties.