The difference, by ear
Hard rock is where the same instincts got organised - tighter, better recorded, riffs written as riffs. Proto-metal is the messy year or two before that.
Both are sung cleanly and move at much the same pace, around 90 to 140 bpm. To hear the difference, play Blue Cheer next to Led Zeppelin. Proto-metal comes from the metal side of the tree and hard rock from the rock side. United States and United Kingdom appear in the origins of both.
In figures
Proto-metal
Where it sits
In short
The heavy bands from before the term existed: over-amplified acid rock, already built around the riff.
How it sounds
- Volume and distortion beyond what the technology of the era allowed, with natural saturation.
- A repeating riff in place of a blues progression, but still inside rock and roll structures.
- Heavy drums up front and vocals in the high register.
Key acts
- Blue Cheer
- Steppenwolf
- Sir Lord Baltimore
- Budgie
Start here
The pickBudgie - Breadfan. Metallica covered it, but the original is stranger.
Full page →Hard rock
Where it sits
Rock › Blues rock › Hard rock
In short
Louder volume, thicker riffs, vocals pushed to the edge. Heavy metal splits off from it, but hard rock stays closer to the blues and to the chorus.
How it sounds
- Riffs built on power chords, with palm muting and constant distortion.
- Vocals pushed into the high register, often right at the edge of a rasp.
- A heavy rhythm section that still grooves - the bass stays melodic rather than doubling the guitar.
Key acts
- Led Zeppelin
- Deep Purple
- AC/DC
- Guns N' Roses
Start here
The pickDeep Purple - Machine Head. Six songs, all essential.
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