Three rock powerhouses released albums on July 2, 1991, which reflected the different yet important states of their respective careers.

For Tom Petty, Into the Great Wide Open represented the merger of two worlds. He was coming off his biggest career success in 1989’s Full Moon Fever. The solo LP, created alongside producer Jeff Lynne, was recorded without Petty’s longtime backing band the Heartbreakers (save for Mike Campbell and the occasional guest appearance). Thanks to radio-friendly hits like “Runnin’ Down a Dream,” “Free Fallin’” and “I Won’t Back Down,” Full Moon Fever sold more than 5 million copies.

"I didn't want to leave the Heartbreakers behind," Petty told Rolling Stone in 1991, "because I figured they were the best band I know, and because it just felt like there was a lot of unfinished business. But at the same time, I knew I was on a roll, and I didn't want to just drop what Jeff and I had going."

As such, Petty brought Lynne in to produce his next LP with the Heartbreakers. Expectations were high, and he knew chemistry would be important.

"Now, that was scary for me," Petty admitted. "There I was taking one of my new friends to meet some of my old ones. And all I can think is 'Oh, boy, these people had better get along.'"

Ultimately, the fusion of these two worlds worked, though perhaps not as well as Petty had hoped.

Into the Great Wide Open was generally well received upon release, spawning two hits in “Learning to Fly” and its title track. Still, many regarded it as a rehash of Full Moon Fever, as the Heartbreakers assimilated rather than truly combined with Petty's new approach.

"Into the Great Wide Open maybe lost the simplicity that Full Moon Fever had," Lynne admitted in Petty: The Biography. "Full Moon Fever had a kind of blatant, this-is-what-it-is-take-it-or-leave-it feeling. The sound was so concise, just one sound that belonged to itself. The next one, Into the Great Wide Open, maybe it was just thought about too much. It wasn't as simple or straightforward."

Criticisms aside, the album was still a commercial success, selling more than 2 million copies in the U.S.

Watch the Video for Tom Petty's 'Learning to Fly'

Also released on July 2, 1991, was Shades of Two Worlds, the 10th LP by the Allman Brothers Band. Unlike Petty – who was soaring to career heights at the time – the Allmans were in the midst of a comeback.

Infighting, drug addiction, creative differences and the deaths of guitarist Duane Allman and bassist Berry Oakley contributed to the band’s heavy baggage over the years. The group finally hit its breaking point and disbanded in the early '80s, following disappointing album sales and continued drama. Still, time heals all wounds: Following a successful reunion tour in 1989, the Allman Brothers Band rebounded with their 1990 LP, Seven Turns. Though sales were modest, the album produced a trio of rock radio hits: "Good Clean Fun," "It Ain't Over Yet" and the title song.

But after nearly a decade away, were the Allman Brothers truly back? Shades of Two Worlds would provide the answer.

Across eight tracks, the LP offered some of the band’s best material since the ‘70s. Much of the credit went to Dickey Betts and Warren Haynes, the latter of whom joined the group when it reunited in 1989. Both contributed heavily to the songwriting for Shades of Two Worlds, adding depth and maturity to the band’s distinctive sound.

Listen to the Allman Brothers Band's 'End of the Line'

While the Allman Brothers were busy sparking their rebirth, July 2, 1991, found Alice Cooper looking to prolong his latest wave of popularity. He had soared back into the mainstream in 1989 thanks to the platinum-selling album Trash and its hit single "Poison."

Part of what made Trash so popular was its many guest appearances - everyone from Jon Bon Jovi to Steven Tyler to Steve Lukather contributed to the LP.

Cooper doubled down on the formula for 1991’s Hey Stoopid, welcoming some of the biggest names in rock onto the album. Steve Vai and Nikki Sixx contributed to “Feed My Frankenstein,” while Sixx’s Motley Crue bandmate Mick Mars performed on “Die for You.” Slash and Ozzy Osbourne appeared on the album’s title track, which also proved to be the most successful single. Joe Satriani was ultimately featured more than any other guest, appearing on five of the album’s songs.

“I used to be very protective about Alice Cooper albums,” Cooper confessed to Metal Forces magazine before the album arrived. "When I was doing School's Out and Billion Dollar Babies, I never would have considered putting another rocker on the record! I always thought Alice had to be so exclusive that he had to be on his own all the way. But I've lost that now.”

Despite all its star power, Hey Stoopid was unable to match its predecessor’s success, stalling at No. 47 on the Billboard chart. Still, the LP remained a favorite of Cooper and his die-hard fans, and was reissued in 2013 with three previously unreleased bonus tracks.

Watch Alice Cooper's Video for 'Hey Stoopid'


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