1001 Albums You Must Hear Before You Die + 1000 Recordings To Hear Before You Die
Led Zeppelin is not metal. It's not the starting point of metal. Don't get me wrong; Zep was loud and outrageously talented, but they played blues-based rock 'n' roll, not heavy metal. I say this because every amateur attempt at a "history of metal" (I'm looking at you, VH1) insists upon focusing on Led Zeppelin, a very palatable choice compared to darker counterparts. There should be no doubt that one band, and one band alone, is the original influence behind every group in every sub-genre that defines itself as "metal." That band is Black Sabbath.
Like so many groups, Sabbath laid out the foundations for its style on its debut album, but the follow-up would go down in history. "Paranoid" revealed much improved songwriting skills that would allow the band to lead an assault on the charts, as well as listener's ears.
Although most associate Black Sabbath with the notorious Ozzy Osbourne, the true star is guitarist Tony Iommi. Iommi is revered as a master of riffs, the predecessor to guitarists like Dimebag Darrell, James Hetfield and Kerry King, all of whom are highly regarded for riff-writing rather than soloing ability. Iommi wasn't the first guitarist to break away from typical blues-based riffs, but the break from blues came to define what was heavy metal and what wasn't. The quality that makes Iommi's riffs so recognizable was a "lucky" accident. The guitarist had two of his fingertips sliced off in an industrial accident, and by tuning his guitar down to drop-D, it allowed him to transition more easily between chords. It also, either purposefully or inadvertently, made his playing much heavier than any mainstream rock before it.
Link Wray gained some acclaim for his drop-D playing in 1958 with "Rumble," and other bands had occasional songs tuned down, but Iommi and Sabbath brought the darkness to the light. Bassist Geezer Butler tuned his instrument to match Iommi's, and the riffs poured forth, from the imposing backdrops of "War Pigs" to the sludgy "Electric Funeral." The masterstroke is of course "Iron Man," one of the most easily recognizable guitar parts of all time. The song derived its title and theme from Osbourne's description that it sounded like "a giant iron bloke walking around."
Sabbath never scores too many points for lyrical content, because with a sound that heavy, the group didn't need it (a trend that has carried on, for better or for worse, in most modern metal). This album brought catchier themes if nothing else. "Iron Man" at least featured a narrative, and the overrated title track gained radio attention. "Hand of Doom" is the most underrated song on the album, describing the horrors of post-traumatic drug addiction.
Again, no offense to Led Zeppelin, The Who, and the whomever. Black Sabbath is terribly under-appreciated (it didn't make the Rock 'n' Roll Hall of Fame until 2006) for its contributions to modern rock music. Any metal band, and a fair share of other "hard rock" outfits owe a lot to this group.
INTERESTING FACT: In Finland, the track "Paranoid" fills a similar role as "Free Bird" in the United States. It is not uncommon to hear obnoxious fans shouting the request, regardless of what concert one is at. I don't know if say shouters get beaten up the same way as at American metal shows.