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Dinosaur Jr. is an American rock band formed in Amherst, Massachusetts, in 1984, originally simply called Dinosaur until legal issues forced a change in name. The band was founded by J Mascis (guitar, vocals, primary songwriter), Lou Barlow (bass, vocals), and Murph (drums). After three albums on independent labels earned the band a reputation as one of the formative influences on American alternative rock, creative tension led to Mascis firing Barlow, who later formed Sebadoh and Folk Implosion. His replacement, Mike Johnson came aboard for three major-label albums.

Dinosaur recorded much of their second album You're Living All Over Me with Sonic Youth engineer Wharton Tiers in New York. During the recording process, tension emerged between Mascis and Murph because Mascis had very specific ideas for the drum parts. Barlow recalled, "J controlled Murph's every drumbeat...And Murph could not handle that. Murph wanted to kill J for the longest time." Gerard Cosloy was excited by the completed album, but was devastated when Mascis told him the band was going to release it on California-based SST Records. Mascis was reluctant to sign a two-album deal with Homestead, but Cosloy felt betrayed, "There was no way I couldn't take it personally." After the album's completion Mascis moved to New York, leaving the rest of the band feeling alienated. You're Living All Over Me was released in 1987; early copies of the record in the Boston area were packaged with the Weed Forestin' tape, the first release by Barlow's side project Sebadoh. The album received much more attention in the indie-rock community than the debut. While the previous record had featured different musical styles for each song, You're Living All Over Me found the band's various disparate influences merging into each individual song. Although the hardcore punk influences were noticeably more muted than on Dinosaur, the overall sound was much more powerful, with the instruments often recorded very loud and with considerable distortion. While Mascis's guitar, alternating between Black Sabbath-like riffs, squalling solos, dissonant noise-rock and occasional quiet passages, was the main attraction, Barlow's bass, melodic, highly distorted and often playing thick two-note chords, competed for attention. Meanwhile, Murph played the Mascis-composed drum parts in a very heavy and powerful fashion, resulting in a version of the power trio format. Mascis did most of the lead singing, in a detached drawl that presented a contrast with the extreme music. The songs were highly melodic, albeit with odd song structures that avoided the typical verse-chorus-verse patterns of most rock and pop songs. Barlow also composed two songs: the hardcore-influenced "Lose" and an acoustic sonic collage entitled "Poledo" that anticipated his work with Sebadoh. Immediately following the release of You're Living All Over Me, supergroup The Dinosaurs (featuring ex-members of Country Joe and the Fish, Quicksilver Messenger Service, Hot Tuna, Grateful Dead and Jefferson Airplane) sued them over the use of the name, prompting the addition of "Jr."

Entity:
Dinosaur Jr.