Heavy metal was facing major changes in 1974, both internally and externally.

Looking from the inside out, neither Black Sabbath nor Led Zeppelin issued new albums in 1974, but Deep Purple released two in an attempt to get fans to ignore the recent dissolution of their classic Mk. II lineup. Meanwhile, a young band from Birmingham named Judas Priest made an unremarkable debut.

Looking from the outside in, glam rock hysteria – or its aftermath, anyway – was influencing all kinds of music in 1974, including the heavy stuff (see Queen, The Sweet, etc.), and it’s no coincidence that this was the year that birthed Kiss, AC/DC, and other future hard rock titans.

But continued sonic experimentation and the resulting mutations were still the order of the day, as you’ll see when you dig into 1974’s Best Heavy Metal Songs You Didn’t Know About.

Scroll through the gallery below and follow this list on Spotify.

'70s Metal: Songs You Didn't Know About - Playlist

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