Judas Priest, performing in 2005

The electric guitar and the sonic power that it projects through amplification has historically been the key element in heavy metal. The lead role of the guitar in heavy metal often collides with the traditional “frontman” or bandleader role of the vocalist, creating a musical tension as the two “contend for dominance” in a spirit of “affectionate rivalry”. Heavy metal “demands the subordination of the voice” to the overall sound of the band. Reflecting metal’s roots in the 1960s counterculture, an “explicit display of emotion” is required from the vocals as a sign of authenticity. Critic Simon Frith claims that the metal singer’s “tone of voice” is more important than the lyrics. Metal vocals vary widely in style, from the multioctave, theatrical approach of Judas Priest’s Rob Halford and Iron Maiden’s Bruce Dickinson, to the gruff style of Motörhead’s Lemmy and Metallica’s James Hetfield, to the growling of many death metal performers.

The prominent role of the bass is also key to the metal sound, and the interplay of bass and guitar is a central element. The bass guitar provides the low-end sound crucial to making the music “heavy”. Metal basslines vary widely in complexity, from holding down a low pedal point as a foundation to doubling complex riffs and licks along with the lead and/or rhythm guitars. Some bands feature the bass as a lead instrument, an approach popularized by Metallica’s Cliff Burton in the early 1980s.

Metallica, performing in 2003

The essence of metal drumming is creating a loud, constant beat for the band using the “trifecta of speed, power, and precision”. Metal drumming “requires an exceptional amount of endurance”, and drummers have to develop “considerable speed, coordination, and dexterity…to play the intricate patterns” used in metal. A characteristic metal drumming technique is the cymbal choke, which consists of striking a cymbal and then immediately silencing it by grabbing it with the other hand (or, in some cases, the same striking hand), producing a burst of sound. The metal drum setup is generally much larger than those employed in other forms of rock music.

In live performance, loudness—an “onslaught of sound,” in sociologist Deena Weinstein’s description—is considered vital. In his book Metalheads, psychologist Jeffrey Arnett refers to heavy metal concerts as “the sensory equivalent of war.” Following the lead set by Jimi Hendrix, Cream and The Who, early heavy metal acts such as Blue Cheer set new benchmarks for volume. As Blue Cheer’s Dick Peterson puts it, “All we knew was we wanted more power.” A 1977 review of a Motörhead concert noted how “excessive volume in particular figured into the band’s impact.” Weinstein makes the case that in the same way that melody is the main element of pop and rhythm is the main focus of house music, powerful sound, timbre, and volume are the key elements of metal. She argues that the loudness is designed to “sweep the listener into the sound” and to provide a “shot of youthful vitality.” Heavy metal’s fixation on loudness was mocked in the rockumentary spoof This Is Spinal Tap, in which a metal guitarist claims to have modified his amplifiers to “go to eleven.”