Metallica will celebrate Record Store Day 2015 by releasing their widely circulated and legendary 1982 demo tape No Life ‘Til Leather on cassette.

At the time, Metallica were just another unsigned metal band fine-tuning their sound, honing their chops and trying to drum up enough attention to get signed by a record label. Back then, before the Internet and especially in the metal scene, options were few. So many artists took the DIY route and recorded their music and sent out their demos to various record companies as well as fellow metal fans across the globe.

In turn, these fans would dub copies of their favorite tapes and share them with other fans in the network, and generating word-of-mouth buzz for fledgling artists. It was this rudimentary system, which seems simultaneously quaint and remarkably effective these days, that would bring Metallica to the attention of their U.S. and U.K. labels, Megaforce and Music for Nations, respectively.

For Metallica, which started forming in 1981 when singer and guitarist James Hetfield and drummer Lars Ulrich first bonded over the New Wave of British Heavy Metal bands they both worshiped, things moved surprisingly fast after they drafted lead guitarist Dave Mustaine and bassist Ron McGovney. Within months, the band had slotted a song (“Hit the Lights,” recorded with pre-Mustaine guitarist Lloyd Grant) onto the first Metal Massacre compilation , worked up a few originals and Diamond Head covers in McGovney’s garage and then cut the four-song Power Metal demo in April 1982.

But it was their next effort, recorded on July 6 that same year, that revealed just how hungry this young quartet was. Named after Motorhead’s 1981 live album No Sleep ’Til Hammersmith, the 30-minute No Life ’Til Leather provided much of the framework for Metallica’s debut album, Kill ‘Em All, which would be released the following year. In fact, all seven of the demo's songs would make it onto first LP, re-recorded with only a few cosmetic alterations — including Mustaine’s solos, which his replacement, Kirk Hammett, was asked to replicate in his more polished and classically informed style.

This is evident on the opening track, “Hit the Lights,” in which Hetfield mimics Diamond Head singer Sean Harris' vocal affectations in the chorus. Otherwise, this version bares all the hallmarks of the more familiar Kill ‘Em All take. “The Mechanix” (penned almost entirely by Mustaine) was later augmented by Hetfield and Ulrich with a slow-tempo mid-section and a completely revised lyric to transform the rough original into the album's immortal “The Four Horsemen.”

There's also the Motorhead-inspired “Motorbreath” (fully formed other than Hammett’s solo revisions and Hetfield’s looser vocals), a notably slower and almost doomy rendition of “Seek and Destroy” and a familiarly frantic “Metal Miltia” -- the demo’s crusty rhythm guitar tones render the razor blade riffs half as sharp but twice as deadly. “Jump in the Fire” (which swings more fluidly here than on Kill ‘Em All), and “Phantom Lord” (which would gain a new intro when re-recorded for the LP) bring the demo to a close.

The only key components responsible for Metallica’s subsequent race to the top still missing here are Hammett and bassist Cliff Burton, who replaced McGovney and contributed to the new songs “No Remorse,” “Whiplash” and his bass solo, “Anesthesia (Pulling Teeth),” for the album. No Life ’Til Leather is essentially three-fourths of Kill ‘Em All and packed with so much revolutionary thrash-metal firepower that it’s no wonder it soon became a tape-trading sensation throughout the global underground metal scene.

Get ready to experience the thrill all over again.

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