The History of Heavy Metal Part I: The Difference Between Metal and Heavy Metal

Heavy metal may be the most misunderstood and misrepresented form of music in Western culture. From the widespread misuse of the term to the insistence by fans, journalists, and musicians that bands playing in seemingly hundreds of different musical styles be included under its canopy, heavy metal causes confusion almost everywhere it goes. Despite common use, the names “metal” and “heavy metal” are not interchangeable; they do not refer to the same music, and one term is not simply a shortened version of the other. Heavy metal is the first form of true metal music, and it deserves to have its name reserved for creations in its signature style. Responsible use of the terms “metal” and “heavy metal” enhances clarity of and appreciation for groundbreaking artists like Judas Priest, Iron Maiden, and Black Sabbath, as well as the hundreds of lesser known heavy metal bands who have contributed valuable creations to the genre.

Because this article goes into detail about differences between styles of metal music, it’s helpful to be familiar with the importance of music genres before moving on. It’s also worth making a distinction upfront between genres, which are broad music categories, and subgenres, which are smaller and more specific styles of music within a genre.

What is Heavy Metal?

holy diver
Dio – Holy Diver (1983)

Heavy metal grew out of hard rock music of the 1970s and flourished throughout the 1980s and early 1990s. It is played almost exclusively with drums, electric guitars, and electric bass, though synthesizers and acoustic guitars are historically prevalent accompaniments. Heavy metal clearly exhibits elements of ‘70s hard rock in its foundation, though it is generally faster and more aggressive in its delivery. It also features greater guitar distortion and frequently leans on steely sound production for its gritty character. Elements of the blues and punk music may also be present: blues influences are commonly heard in the guitar riffs and solos, while punk music reveals itself in the speed of the songs and the rebellious, sometimes violent attitude of the music.

Heavy metal is typified by soaring, clean vocals, though numerous instances of coarse baritones also exist. Importantly, heavy metal is melodic, and on a structural level, is a form of pop music. Songs typically follow an ABABCBB format in which A is the verse, B is the chorus, and C is a bridge or, almost always, a guitar solo. Like pop music, the songs feature memorable chorus hooks and prominent, recurring instrumental melodies.

In addition to ‘80s releases from Black Sabbath, Judas Priest, and Iron Maiden, examples of music at the very heart of true heavy metal include Dio’s Holy Diver and Accept’s Balls to the Wall, both from 1983. Armored Saint’s 1984 album March of the Saint and Savatage’s 1985 album Power of the Night are similarly excellent examples of heavy metal, even though these bands later evolved into power metal and progressive metal, respectively. In fact, if there’s a single song that can accurately represent the sound of heavy metal, it’s Savatage’s “Power of the Night.”

It’s useful to note there are few, if any, clean breaks between heavy metal and closely related music styles. It’s entirely possible to line up songs and albums to form a continuous musical spectrum from one metal subgenre into another, such as heavy-power-thrash-death-black, and the boundaries of heavy metal blur significantly as the music moves toward nearby metal styles. The greatest gray area is between heavy metal and speed metal, including acts like Liege Lord and late ‘80s-era Running Wild, as well as American power metal, including ‘80s releases from bands like Vicious Rumors and Chastain. Because many speed metal and American power metal releases display relatively small evolutions, they can often be classified within the boundaries of heavy metal.

Additionally, heavy metal overlaps in considerable amounts with doom, thrash metal, European power metal, and early progressive metal. There is also a small but historically significant connection between heavy metal and black metal. For this reason, many albums can be classified in multiple metal subgenres or described with hybrid terms. A perfect example of this is Sanctuary’s 1988 album Refuge Denied, which is a roughly equal mix of heavy metal, thrash metal, and American power metal. Also, although the vast majority of bands in history fall cleanly within the boundaries of either hard rock or heavy metal, a small gray area between the two genres has persisted from the late ‘70s into the present.

Despite the elitism that is sometimes present in the term, “true heavy metal” is a useful descriptor for separating bands that play near the center of the subgenre from acts with a hybrid or evolved sound. This is often relevant even within a single band’s discography. For example, Black Sabbath’s 1981 album Mob Rules is a true heavy metal album, while their 2013 album 13 is a blend of heavy doom. Similarly, Armored Saint’s 1984 album March of the Saint is a true heavy metal album, while their 1991 release Symbol of Salvation falls within the scope of American power metal. It’s not necessarily inaccurate to call these bands’ later releases “heavy metal,” but they exist outside the nucleus of the style. “True heavy metal,” and the slightly less provocative term, “traditional heavy metal,” are also necessary and relevant labels for separating the music from other metal subgenres and non-metal genres that are mistakenly grouped under the heavy metal banner.

Equally important to the understanding of what is heavy metal is the understanding of what is not heavy metal. In terms of instrumentation, heavy metal does not use symphonies or a synthesizer’s approximation thereof. It does not contain influences from classical music, nor does it include opera-style vocals. Heavy metal does not feature Latin rhythms or South American folk instruments. It does not employ any type of music sampling or turntables. Heavy metal does not use hip-hop vocal deliveries, nor does it include coarse, strident singing like the kinds found in death metal, black metal, and some thrash metal. It does not include industrial rhythms or other strong use of synthesizers. Labels like “symphonic metal” and “electronic metal” are contradictions in terms, and most bands in those categories deserve better and original genre labels for their diverse sounds and willingness to explore new musical territory.

The vast majority of heavy metal albums were released between 1980 and 1992, though the style has seen a significant revival since 2008, appropriately known as the new wave of traditional heavy metal (NWOTHM). The years in-between saw very few true heavy metal albums. If there are any doubts about a recording from the ‘90s and ‘00s, it is safe to assume it is not heavy metal. This Traditional Heavy Metal playlist offers an in-depth collection of releases within the genre, and it focuses on quality recordings with mid to high production values. All albums and songs within the playlist can be accurately described as heavy metal, even if they contain influences of other subgenres like speed metal or American power metal, and the playlist is a valuable resource and crash course for the uninitiated.

In the shortest terms possible, metal is a genre of music, and heavy metal is a specific subgenre of metal, just like thrash metal or death metal. It makes no more sense to call all forms of metal “heavy metal” than it does to call them all “black metal,” yet the confusion persists. There is a reasonable historical precedent for this, which is that heavy metal was the first true form of metal music, but the rampant misuse of the label should have been resolved long ago. Hundreds of heavy metal albums have been produced in the past several decades, including groundbreaking entries that remain influential to modern artists playing a diverse range of music. Using the term “heavy metal” to describe dissimilar and even unrelated musical styles disregards the innovation of these releases, diminishes the significance of the music as its own entity, and causes unnecessary confusion in conversations. For these reasons and more, it is well past time heavy metal reclaimed its rightful name.

The Roots of Heavy Metal

In order to fully understand the characteristics and sound of heavy metal, it is necessary to go over the early history of the metal genre and its relationship with rock music, particularly the years from 1970 to 1980. Through this process, it must be emphasized that music genres and subgenres shift rapidly when they are new and grow increasingly rigid over time as a greater volume of music is created in and around them. The following commentary therefore benefits from hindsight and broadly considers metal and rock music with decades worth of contributions in mind. Additionally, the decision about a song or album’s classification must ultimately be made in relation to the music around it. Boundary lines between genres and subgenres are formed in response to the density and saturation of each style, and specific songs are classified based on their nearness to the center of each one.

For example, in the diagram below, there is a slight musical overlap between hard rock and heavy metal. Outside of that overlap, there is a moderate amount of music within hard rock that is musically very close to metal. It would be easy to classify that music as metal given its proximity to the genre. However, when rock and metal are considered in their entirety, it’s clear the music has much more in common with rock than metal and should be classified accordingly. Specific examples of this will be provided later.

genre diagram 1
A sample diagram of heavy metal and closely related musical styles. It is impossible to completely and accurately classify music in this way, and the diagram is therefore meant as a visualization tool and not a concrete classification system. Use this glossary for more information on genres and subgenres.

Since the point in question of this article is the name “heavy metal” and its usage, it’s helpful to start with the etymology of the term as it applies to music. In the late ‘60s, the words “heavy,” and very occasionally, “heavy metal,” began to be tossed around in song lyrics and descriptions of music, especially in hard rock. When Black Sabbath’s 1970 self-titled debut was released, it became a magnet for the terms due to the band’s uniquely ponderous sound.

The newness of Sabbath’s playing style and the still very loose application of the words “heavy” and “heavy metal” caused writers and fans to commonly use them interchangeably with “rock” and “hard rock” to describe music throughout the ‘70s. From a historical perspective, this proves to be a justifiable bit of ambiguity, especially as the majority of Sabbath’s songs, especially those released between 1973 and 1978, fell much closer to acid rock and bluesy hard rock than later forms of metal.

Most other ‘70s bands saddled with the “heavy metal” tag were even closer stylistically to the heart of rock music than Sabbath was. For example, Led Zeppelin had a milder, bluesier sound with prominent elements of American folk music, Deep Purple had a feel-good roadhouse rock vibe that was often too light to even be classified as hard rock, and Aerosmith played a strong mix of blues and hard rock that was an immediate evolution of ‘60s rock acts like The Rolling Stones. Although these bands were each making significant contributions to music history, their styles fall within the scope of rock and hard rock and therefore need no new genres to classify them.

In contrast with contemporary bands of the era, it’s clear that Black Sabbath pioneered a new approach to songwriting and audio production in the ‘70s, one that ultimately laid the foundation for the metal genre. However, saying that Black Sabbath was the first metal band is a massive oversimplification of the various evolutions of the group and their music, as well as their role in the development of the metal genre.

Black Sabbath

black sabbath
Black Sabbath – Black Sabbath (1970)

Prior to 1969, Black Sabbath played a brand of bluesy hard rock with a deeply distorted guitar sound under the band name Earth, and before that as an even less rock-oriented incarnation as the Polka Tulk Blues Band. In 1969, the band overhauled their sound, as well as their conceptual themes, under the Black Sabbath moniker, choosing to focus on instrumental distortion and the grinding, leaden sound they had recently developed.

Notably, the pioneering new sound heard on Sabbath’s first four albums — 1970’s Black Sabbath and Paranoid, 1971’s Master of Reality, and 1972’s Vol. 4 — were more formative to doom metal than to heavy metal. The achingly downtempo, trudging delivery of tracks like “Black Sabbath” and “Electric Funeral” bear virtually no resemblance to the heavy metal bands that emerged a decade later. However, their influence can be heard prominently in the songs of ‘80s true doom acts Pentagram and Candlemass, such as on Pentagram’s “When the Screams Come,” as well as in the gothic death-doom of early ‘90s Paradise Lost songs like “Rotting Misery” and “The Painless.”

Sabbath’s next two releases of the decade, 1973’s Sabbath Bloody Sabbath and 1975’s Sabotage, notably backed off the group’s signature gloomy style for a more fanciful, acid-washed rock sound with experimental use of synthesizers and a return to bluesy, jam-style instrumental sections. Black Sabbath continued the decade with an even greater regression, delivering playful, Beatles-esque rock music on 1976’s Technical Ecstasy that was almost unrecognizable from their debut. 1978’s Never Say Die! revived some of Sabbath’s heaviness, though the music frequently fell into soft, dreamy spaces and was missing much of the attitude and energy of other albums from the same year.

This move away from Sabbath’s trademark heavy sound further complicated discussions about heavy metal and led to an understandable, if completely mistaken, jump in logic: if Black Sabbath was considered a heavy metal band, yet played lighthearted rock music like “Looking for Today” and “A Hard Road,” then bands like Deep Purple and Heart should be classified as heavy metal as well.

However, despite the growing confusion, heavy metal was actually moving much closer to a clear identity and definition thanks to innovative releases from Rainbow and Judas Priest in the late ‘70s.

Rainbow and Judas Priest

rainbow rising
Rainbow – Rising (1976)

As Black Sabbath turned away from their construction of a new music genre, a handful of other bands picked up where they left off and began paving the way toward true metal. These creators notably played a very different style of music from Sabbath’s pre-doom tracks, and their releases in the second half of the ‘70s were immediate and direct precursors to true heavy metal. Foremost among these acts are Rainbow and Judas Priest. Rainbow’s 1976 album Rising and 1978 follow-up Long Live Rock ‘n’ Roll, as well as Judas Priest’s final two releases of the decade, 1978’s Stained Class and Killing Machine (later released as Hell Bent for Leather), pointed the way to an exciting and innovative new sound.

Although these albums can roughly be classified as hard rock, they focused on tighter instrumentation and more energetic songwriting than almost all hard rock that had come before–including Sabbath’s early recordings and previous releases from Judas Priest and Rainbow themselves. Significantly, they also dropped nearly all of the blues influences within hard rock for a more direct and assertive approach to their music. These recordings embraced an upbeat, rollicking sound driven by power chords, invigorating guitar solos, and catchy vocal hooks, all packed into accessible pop song structures.

Other significant efforts from the late ‘70s featuring this new, vigorous sound include Scorpions’ 1979 album Lovedrive and Saxon’s self-titled debut from the same year, both of which exist on the fringes of hard rock where the genre blends into heavy metal. Incidentally, with the exception of Judas Priest, each of these heavy metal pioneers would shift into lighter, hard rock sounds in the ‘80s, effectively turning over the job of constructing heavy metal once again to other artists.

Returning to the diagram from earlier, it’s possible to see where Sabbath’s Paranoid and several late ‘70s albums land in the broad scope of rock and metal. Rainbow’s Long Live Rock ‘n’ Roll and Judas Priest’s Hell Bent for Leather form the boundary line between heavy metal and hard rock.

genre diagram 2

Although the term “heavy metal” had been in use for over a decade, it never had a consistent or concrete musical style to attach itself to, and the term remained more or less undefined throughout the ‘70s. However, the seeds of heavy metal, first planted by Black Sabbath and nurtured by acts like Rainbow and Judas Priest, were on the verge of sprouting into the first true heavy metal creations.

The Birth of Heavy Metal

british steel
Judas Priest – British Steel (1980)

1980 is the critical year in metal’s evolution, when the ideas percolating around heavy music coalesced and solidified into an undeniably new form of music. This effort was spearheaded by three seminal recordings: Black Sabbath’s Heaven and Hell, Judas Priest’s British Steel, and Iron Maiden’s Iron Maiden. These recordings established a bold new sound that effectively hacked away at their hard rock roots and further severed ties with the blues. 1980 also saw a small number of releases that were a mix of this new heavy metal sound and the older sounds of hard rock. Two notable examples in this group are Saxon’s Strong Arm of the Law and Accept’s I’m a Rebel.

Each of the 1980 albums from Sabbath, Priest, and Maiden is remarkable for the trajectory of music it followed and the precedent it established. Black Sabbath had recently fired Ozzy Osbourne and set out to redefine themselves with a new and improved singer in Rainbow’s Ronnie James Dio. The revamped sound they revealed on Heaven and Hell was strikingly different from the loose, softhearted rock on the band’s last two albums and nearly as different from the rest of their discography.

Where Ozzy droned, Dio soared, and Heaven and Hell displayed an element of imagination and mysticism rarely heard from the band previously. It borrowed heavily from Rainbow’s musical delivery, and the new songwriting was cleaner, tighter, faster, and significantly more deliberate than before. Notably, the production was also thicker and heavier than on albums from Rainbow and other hard rock acts of the ‘70s.

Gone were Sabbath’s expressive jam sessions packed with bluesy guitar work. Gone were Sabbath’s trudging, downtempo pieces that pounded away through their duration like the band members were literally made of iron. In their stead were serious-minded, carefully composed pieces with well orchestrated breaks and guitar solos. Fluid, uptempo tracks like “Neon Knights” and “Die Young” remain archetypal examples of true heavy metal.

Judas Priest similarly unveiled a new sound in 1980. The band had steadily shifted from the romantic, occasionally progressive rock sound of mid-‘70s releases Rocka Rolla and Sad Wings of Destiny to forge a new and heavier style of music with each release throughout the ‘70s. This pattern of evolution brought them to the grounded and rough-hewn song structures of the impossibly influential British Steel. It was the most aggressive recording from the band to date, with tracks like “Rapid Fire” and “Steeler” kicking up the tempo and aggression beyond anything else from the band’s discography. To accent the energetic new songwriting, British Steel‘s production was notably thicker and more rugged than on Stained Class and Hell Bent for Leather, delivering dynamic percussion, crunchy rhythm guitars, and screaming guitar solos that remain the exemplary sound of heavy metal.

Iron Maiden, the youngest band of the three, and the only one without a formal release to their name, unquestionably brought with them the most energy and speed, quickly attracting a following from disenchanted fans roaming a fractured British punk music scene. Of the three pivotal contributions made in 1980, Iron Maiden’s self-titled debut had the lightest sound, though the energy and attitude of the music was frequently far removed from hard rock and contained virtually no traces of the blues. It was not until the band’s 1982 release, The Number of the Beast, that they would cement themselves as a true heavy metal band, though their first two recordings remain pivotal creations at the dawn of the new musical style.

Although the term “heavy metal” had continued to be loosely attributed to British hard rock acts like Def Leppard, Whitesnake, and AC/DC, the unmistakable demarcation line established in 1980 redefined the name. In a single year, the term “heavy metal” that floated around in a nebulous state for an entire decade had found its proper home. Three musically distinct — yet ideologically congruent — albums represented a lucid new form of music that stood apart from nearly everything that had come before them, and they would establish the foundation for all true metal releases to follow. The bold sound of these recordings, along with their immediate follow-ups from all three bands in 1981, helped ignite a rapid proliferation and diversification of metal in the early ‘80s.

The heavy metal sound was represented on hundreds of albums throughout the decade from bands around the world. Some artists, like Armored Saint, Savatage, and Queensrÿche, signed to major labels and produced polished recordings with commercial appeal. Many more released their records independently or through small record labels, opting for gritty production with harsh, dungeon-like sound quality. In many cases, these unrecognized bands only produced one or two albums before disbanding or moving on to more profitable music endeavors. Early releases from Steel Vengeance, Running Wild, Stormwitch, and Warlock represent this underground heavy metal sound. Along with other underground artists who blended their sound with newer and more aggressive styles like thrash and speed metal, these bands collectively form the ironclad, uncompromising sound of ‘80s underground metal that remains the primordial soup and spiritual heart of all metal music.

The Metal Explosion

megadeth rust in peace copy
Medadeth – Rust in Peace (1990)

As heavy metal flourished over the next few years, it began to evolve quickly at the edges, creating strikingly new forms of music. However, because the splinter styles were fundamentally rooted in heavy metal, they adopted similar names: thrash metal, death metal, power metal, etc. Each year of the ‘80s introduced music with more aggressive, more technical, and more extreme sounds, and suddenly the term “heavy metal” that loosely applied to early outgrowths of the style was no longer relevant to a significant number of new bands.

An accessible example of this rapid evolution, and the confusion that accompanied it, comes in the form of Slayer’s first three full-length recordings. It was not inconceivable at the time to classify Slayer’s 1983 debut Show No Mercy as heavy metal given that Tom Araya’s high-pitched wails and the group’s articulate riffing and rhythms still held notable similarities to NWOBHM, and especially to the emerging speed metal sound, which itself was a more subtle outgrowth of heavy metal. With few other albums to compare it to, Slayer often and understandably received the heavy metal label. By 1985 and the band’s follow-up Hell Awaits, the term was stretched beyond its breaking point. One short year after that, “heavy metal” proved to be a useless label to describe the raucous, frenetic style exhibited on Reign in Blood. Despite the fact the album was undeniably distinct from the heavy metal records that preceded it, it continued to be lumped in with the older style of music.

Another look at the diagram shows several evolutions of metal through albums released during the ‘80s, including Slayer’s first and third albums.

genre diagram 3

By 1990, the metal genre had expanded to include music that exhibited dramatic evolutions of those pivotal 1980 releases, such as Morbid Angel’s Altars of Madness and Megadeth’s Rust in Peace. It became increasingly common to refer to the music collectively as simply “metal.” This made sense, as all the subgenres of the newly expanded metal genre had their respective adjectives. Also, because they still retained variously identifiable earmarks of those seminal 1980 albums, even on the most aggressive recordings, they were still metal. However, the term “heavy metal” continued to be used redundantly for all outgrowths of the original style despite the fact it only applied to the songwriting approach of a slice of the now immense and immensely popular metal genre.

Just as it would be bizarre to say that Iron Maiden played thrash metal or death metal, it was confusing and inaccurate to refer to acts like Kreator and Carcass as heavy metal. Yet people persisted. There is a certain amount of laziness and lack of imagination to blame for this, though the swift rate of musical evolution within metal music was also a culprit for the rampant misunderstanding and misuse of terms. However, that excuse is a limited one. By the time metal in the US yielded to several types of magma during the ‘90s, it became particularly odd for fans, journalists, and TV personalities to slap the heavy metal name on albums that held little or no stylistic connection to the broader metal genre, let alone to heavy metal. No one had insisted on classifying acts like Death and Obituary as hard rock, yet mystifyingly, acts like Slipknot and Machine Head received the heavy metal label.

What’s in a Name?

30 years after the widespread proliferation of metal music and the development of clear distinctions between its largest subgenres, there are no reasonable justifications for calling bands in diverse musical styles like Arch Enemy, Slipknot, and Fleshgod Apocalypse “heavy metal.” Without getting into the conversation of whether those bands are metal at all (that deserves its own topic and will come in The History of Heavy Metal Part II), it is enough to say that, from the standpoints of history and music progression, they are not heavy metal.

Music evolves and demands unique descriptors to acknowledge artists’ innovations. In the 21st century, “metal” is the only accurate term for talking broadly about the metal genre, and it’s well past time “heavy metal” was reserved solely for bands who play in a style similar to the pivotal albums from the early 1980s. To use it otherwise is the same as saying BB King performed African spirituals or that Led Zeppelin was a country folk act.

The misuse of the term is a disservice to the hundreds of excellent heavy metal bands that have contributed to the massive and influential style of music, including pioneers who laid the groundwork for the entire metal genre. It also disregards the innovations and creativity of acts that followed and developed divergent and original music styles. In order to respect all of these creations, metal fans, musicians, and journalists need to treat the terms “metal” and “heavy metal” as the distinctive descriptors they are. Heavy metal is the first and foremost form of true metal music, and there should be no ambiguity about its characteristics or its valuable role in music history.

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