The Razor and the Speaker
Hard rock begins with vandalism. In 1958, Link Wray punctured the speaker cone of his amplifier with a pencil while recording the instrumental Rumble, producing a fuzzed-out growl that no commercial equipment could reproduce at the time. The record was banned from radio in several markets on the grounds that an instrumental, with no lyrics at all, sounded too menacing. Pete Townshend later said he never would have picked up a guitar if not for Wray and that single track.
Six years later in Muswell Hill, London, Dave Davies of the Kinks took the idea further. Depressed and fooling with a Gillette razor blade, he sliced into the speaker cone of his Elpico amplifier, a six-to-eight-watt unit bought from a shop two doors from his house, then ran it into a Vox AC30 for volume. The distorted roar on You Really Got Me followed, recorded at Pye Studios in 1964.
Tubes, Volume, and the Marshall Stack
The enabling technology was the Marshall amplifier. Jim Marshall, a drum teacher and shop owner in Hanwell, west London, began building amps in 1962 with technician Ken Bran and intern Dudley Craven. Their JTM45, based on the Fender Bassman circuit, used different tubes and transformers, producing distortion from the valves rather than from speaker breakup. Tube overdrive sustained and responded to touch in ways a torn cone could not.
Pete Townshend asked for more volume. Marshall built a 100-watt head and an 8x12 cabinet so unwieldy it split into two 4x12 units stacked vertically. By 1968, the Superlead “Plexi” had become the standard for Hendrix, Clapton, and Page. Hendrix pushed it hardest, running his near maximum while keeping the guitar’s volume at 75 to 85 percent, controlling feedback with one hand on the volume knob and the other on the tremolo bar. His tone stack had been modified (56k resistor swapped for 33k, capacitor doubled to 500pf), boosting treble and thickening low-mids. Combined with a Fuzz Face and Vox wah, it breathed.
The Riff as Architecture
Hard rock codified the guitar riff as a song’s structural foundation. The riff outlines a chord progression while functioning as the primary melodic element, and the best ones are identifiable from a single bar: Smoke on the Water, Whole Lotta Love, Back in Black.
Deep Purple’s Machine Head, the source of that first riff, exists because of arson. The band arrived in Montreux in December 1971 to record at the Casino using the Rolling Stones Mobile Studio. On December 4, during a Frank Zappa concert, an audience member fired a flare gun into the ceiling. The Casino burned to the ground. Deep Purple watched smoke drift across Lake Geneva, then relocated to the empty Grand Hotel, tracking the entire album in a corridor off the main lobby.
The Stairwell and the Factory
Led Zeppelin’s recording methods became as influential as their songs. For their fourth album in 1971, Jimmy Page moved the band into Headley Grange, a former poorhouse in Hampshire. For When the Levee Breaks, engineer Andy Johns placed Bonham’s kit in the three-story entrance hall and hung two Beyerdynamic M160 ribbon microphones from the top of the stairwell; those were the only mics on the drums. Johns compressed the signal through Helios F760 limiters, adding a Binson Echorec for the rhythmic breathing effect. That drum sound has been sampled more than almost any other in recorded music.
Tony Iommi of Black Sabbath lost the tips of his middle and ring fingers on his fretting hand in a sheet metal guillotine on his last day at a Birmingham factory. He was seventeen. He fashioned prosthetic fingertips from a melted-down Fairy Liquid bottle, shaped with a soldering iron and covered in leather from an old jacket. The thimbles deadened his feel, so he pressed harder and used banjo strings because light-gauge sets did not exist yet. By Master of Reality in 1971, he had detuned three half-steps to C-sharp to ease the tension. The lower tuning, combined with a modified Rangemaster treble booster and a Laney LA100BL, produced the darkest, heaviest guitar tone anyone had heard.
Eric Clapton had introduced the “woman tone” earlier, on Cream’s Disraeli Gears, recorded in four days at Atlantic Studios in New York with producer Felix Pappalardi and engineer Tom Dowd. Neck pickup, volume at 10, tone control rolled to 1: the eliminated treble removed pick attack, leaving smooth, vocal-like sustain through a Gibson SG and Marshall JTM45/100.
Twin Leads and the Arena
Thin Lizzy’s Scott Gorham and Brian Robertson, hired simultaneously in 1974, developed the twin-guitar harmony that became the band’s calling card. The sound originated by accident: Robertson recorded a single line, and the engineer’s tape delay fed back on itself in harmony. Gorham began writing dual lines at structural peaks, creating a second hook beneath Phil Lynott’s vocals. Jailbreak in 1976 directly influenced Iron Maiden, Judas Priest, and UFO.
Hard rock drove the evolution of live sound. PA systems grew from club rigs to arena-filling monsters; by December 1973, Emerson, Lake and Palmer’s Madison Square Garden shows required a 28,000-watt quadraphonic system and five hours of load-in.
Breaking the Template
Eddie Van Halen rewrote hard rock guitar on a single debut. Van Halen, recorded at Sunset Sound in late 1977 for about $40,000, was mostly cut live. His “brown sound” came from a secondhand 1967 Marshall Plexi imported from England. Built for 230-volt UK power, it ran quietly on 110-volt American current, so he added a Variac transformer: 60 volts for small clubs, 89 for the studio sweet spot. The guitar was a homemade hybrid, a Stratocaster body with a single PAF humbucker. His two-handed tapping on Eruption predated him as a technique, but no one had deployed it with that speed or musicality.
Heart, led by Ann and Nancy Wilson, became one of the first hard rock acts fronted by women to sustain major commercial success. Suzi Quatro had preceded them in 1973 as the first woman to reach rock stardom while playing her own instrument. Joan Jett took the Runaways’ all-female template into a solo career that peaked with I Love Rock ‘n’ Roll at number three on the 1982 year-end chart.
By the time AC/DC recorded Back in Black at Compass Point Studios in the Bahamas in April 1980 with producer Mutt Lange, the formula had reached its purest distillation. Angus Young played a 1971 Gibson SG Standard through a Marshall 1959 Super Lead and a rarer JTM50 with a solid-state rectifier for tighter punch. Engineer Tony Platt summarized the recipe: a Marshall amp, a Marshall cabinet, a Gibson SG, and Angus.
Essential Listening
- Led Zeppelin – Led Zeppelin IV (1971)
- Deep Purple – Machine Head (1972)
- Black Sabbath – Master of Reality (1971)
- AC/DC – Back in Black (1980)
- Van Halen – Van Halen (1978)
- Cream – Disraeli Gears (1967)
- Aerosmith – Rocks (1976)
- Thin Lizzy – Jailbreak (1976)
- Free – Fire and Water (1970)
- Heart – Dreamboat Annie (1975)
- The Jimi Hendrix Experience – Are You Experienced (1967)
- Queen – A Night at the Opera (1975)