One of the best-selling metal albums of all time is unquestionably Metallica's self-titled offering - often referred to as "The Black Album", reports Greg Prato for Ultimate-Guitar.com. Released on August 12, 1991, the twelve-track album - which was produced by Bob Rock, James Hetfield, and Lars Ulrich - spawned some of the band's best-known tracks, including "Enter Sandman," "The Unforgiven," "Nothing Else Matters," "Wherever I May Roam," and "Sad But True." At last count, "The Black Album" has sold over 23 million copies worldwide.

And with several songs having never left the public consciousness – having constantly remained in the band's concert setlists, still being played on rock radio, blasted at sports events, etc. – it's a bit difficult to recall a time when even non-metal fans could instantly hum the "Enter Sandman" riff upon command. But there was indeed a time way back when it was still newly born – which I explored in my 2015 book, Survival Of The Fittest: Heavy Metal In The 1990s." Below are quotes from several renowned rock names recounting hearing the mega-selling LP for the first time and their initial thoughts.

Flotsam And Jetsam guitarist Michael Gilbert: "I remember hearing 'Enter Sandman' on the radio for the first time, and I just got the chills. I was like, 'This is Metallica and it's the biggest thing that I've heard ever as far as metal' - for what we were all doing. I had a lot of emotions about that, because my friend is in that band [then-Metallica bassist Jason Newsted was an early member of Flotsam And Jetsam]. When I heard 'Enter Sandman,' I knew it was going to take them to another level of success, which it did - it took them to ten more levels of success."

Testament frontman Chuck Billy: "I did [know the album would be huge] when I heard the first single and seen the video, 'Enter Sandman'. I remember that night, we were at the gym - we had a basketball league, and the game was over, and the Metallica debut song was on tonight, so we all rushed to the TV at the gym, and 'Enter Sandman' came on. When I first heard it, I was like, 'Holy shit! This is sonically massive.' It just totally blew my mind when I first heard it. And at that point, after it came out, you kind of knew that that record was the 'Metallica masterpiece,' for sure."

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