Two fingertips and a new sound
On his last day working at a sheet-metal factory in Birmingham, the teenage Tony Iommi caught his right hand in a machine and lost the tips of two fingers. He played guitar left-handed, so those were the fingers he pressed the strings with, and he almost gave up. Instead he made thimbles from a melted plastic washing-up bottle, covered them with leather, and switched to lighter strings so they were easier to hold down. Later he tuned the whole guitar lower to slacken them further.
Those loose, low strings are part of why Black Sabbath sounded darker and heavier than anything else around in 1970. Tuning down is now standard across HEAVY METAL: a factory accident helped invent a genre.
The interval they called the devil
Sabbath's first song opens with three notes spread out in a way that sounds deeply uneasy. The gap between them is the tritone, which medieval musicians nicknamed 'the devil in music'. Stories that the church banned it are exaggerated — it was avoided because it is awkward to sing, not because of any law — but it unsettles the ear in a way that suits metal perfectly.
There is real engineering under the noise. DISTORTION means deliberately overloading the amplifier so the guitar snarls instead of ringing. A POWERCHORD works so well with it because it uses only two or three notes: fewer notes means less mush, so the chord stays clear no matter how hard the sound is pushed. A SHRED solo or a screaming WHAMMY dive on top takes years of practice.
How hard should you headbang?
In 2008 two Australian researchers studied the risks to the HEADBANGER and published their findings in a medical journal's Christmas issue. They calculated that the danger to your neck rises with both the tempo of the song and the angle of the swing, worked out that a typical metal song runs at about 146 beats per minute, and suggested fans keep their head movement under roughly 75 degrees — or wear a neck brace. The paper was a joke with real maths inside it. The sore necks are real too.
Metal has a map
The music travels further than people expect. Germany's Wacken Open Air festival brings around 85,000 fans to a village of a couple of thousand people every summer. Finland is often said to have more metal bands for its population than anywhere else, and even has a children's metal band, Hevisaurus, whose members dress as dinosaurs. Scenes thrive in Indonesia, Japan and Brazil, and the SPIKES-and-STUDS uniform is recognisable in all of them.
It keeps splitting into new styles, too, each one usually faster or heavier than the last. THRASH sped everything up in the 1980s, and extreme styles brought the BLASTBEAT, where hands and feet hit almost as fast as a drummer can move — the record for drum strokes in a single minute stands at over 1,200.
The horned hand sign fans throw is older than the music. Ronnie James Dio, who sang for Black Sabbath after Ozzy Osbourne left, said he borrowed it from his Italian grandmother, who used it to ward off the evil eye.