I don't know what you think but I am one of those ballbreaking metalheads that are used to consider the so-called speed metal and thrash metal as two different genres. Despite this, there are no real differences between them for many other persons with the result that they uses the term "speed metal" as synonim of the thrash metal. But the question was more confusing during the mighty '80s when, to mention a notable example, Metallica were described as a speed metal band if not even a power metal band, just because they titled "Power Metal" an obscure demo of their early days thanks to an idea of their bassist Ron McGovney. Therefore, speed metal is considered by many not a real metal genre but a definition born and dead in the '80s.
In general, speed metal is to be considered like a kind of sped up pure heavy metal that's more linear and less violent if compared to thrash metal, that, instead, is a lethal combination between the pure heavy metal and punk/HC, so the style created by bands like Slayer or Metallica is more nervous and ferocius than in the speed metal way. To name two examples so to understand better all these differences, speed metal is represented by "Heavy Metal Maniac" of the Canadians Exciter while thrash by "Kill 'Em All" of Metallica, both albums released in 1983 and both expressions of a very fast metal, just played in two different ways: in fact, the first one is more epic and metallic while the latter one is more scrapping and punkish. And still, Metallica and Slayer (so, the entire thrash metal movement) reached the worldwide reputation (and a bunch of money!) in very few years while Exciter and Impaler (ergo, the speed metal) became cult bands adored by the most metal fundamentalists.
The far origins of both speed and thrash metal were into the '80s, in particular due to the fast "Exciter" (1978) of Judas Priest. This is a song elegant but brutal (granted, for the standards of those times!) to be included also as one of the very first examples of the use of the double kick drum bass in rock music. But, for the truth, the '70s were a good time for single songs able to challenge the listeners in terms of speed and aggressiveness, even by the most unthinkable bands. For example and going beyond the usual suspects Deep Purple ("Speed King", "Fireball", "Hard Lovin' Man"...), comes to my mind numbers as "Frustration" of Jerusalem (their first and last 1972 album was produced by nothing else than Ian Gillan!), the schizophrenic and hyper-aggressive "Plastic Shotgun" of the Germans Night Sun (1972), the proto-motörheadian street metal of "Damned Flame" of the Belgians Blast (1973) or, finally, the very hard "Stone Cold Crazy" even by Queen (1974)!
But all these aforementioned examples were only isolated episodes made by bands that experimented new killing tempos without creating a movement focused on fast songs and neither proposing a systematical codification of the speed/thrash metal, destined to starting from 1983 also if preceded 3 years before thanks especially to "Ace of Spades" of Motörhead.
So, here you are a short story about the proto-speed/thrash metal from 1980 to 1983, and we will focused especially on the bands that believed so much in the speed that this one became (more or less) their belief.
Anyway, our journey doesn't starts already with that seminal aforementioned album but with one of the main NWOBHM bands that was very unlucky at that time despite some very encouraging premises: Diamond Head.
So let's start with "Lighting to the Nations", their fundamental debut album self-produced for their own label Happy Face Records and originally issued in 1000 copies without a real cover artwork (in fact, it was completely white) nor a tracklist and a title with the result that the album was known initially as "The White Album"...but it wasn't the album with the same title of The Beatles! But, fortunately, "Lighting to the Nations" was destined to be reissued a bunch of times in the following years with different cover artworks, also by extreme metal labels like Metal Blade Records in 1994.
With this album, we are in presence of a band that can be described as the heavy metal version of Led Zeppelin, as shown very much by the orgasmic vocals à la Robert Plant of the singer Sean Taylor. But the bands express this big influence through very hard songs that are, at the same time, also refined, complex and incredibly long in according to an enough strong progressive approach with the addition of even two very fast and angry songs. I am talking about "The Prince" (that contains a strange slowdown with a dance/pop vibe!) and the conclusive "Helpless", so powerful in its punkish intensity that it need no guitar solos.
But then, there is the famous "Am I Evil?", a very heavy number that starts in a way very close to Black Sabbath, then it proceed in a hard proto-thrashing mid-tempo just to explode soon after in a majestic tone especially due to the guitarist Brian Tatler, literally on fire with one of his dripping neo-classical guitar solos. It's important to say that the song, helped by the relating videoclip, became the war-horse of Diamond Head, so they even re-recorded it for their sophomore album "Borrowed Time" (a prog masterpice in the NWOBHM period), released in 1982 by the major MCA. Hence, it wasn't surprising that Metallica, always busy to homage their idols, coverized some years later just "Am I Evil?", and this happened in a period where Diamond Head became victims of their own fame and of a major label like MCA, that at time discharged many good NWOBHM bands from Fist to Tygers of Pan Tang.
Bannermen of the metallic purity, the prolific Saxon were very luckier if compared to Diamond Head. In the years 1980-1981, Saxon released an unrepeatable trilogy of classics composed of "Wheels of Steel", "Denim and Leather" and "Strong Arm of the Law", each one released by Carrere Records, a small label owned by a French man named Claude Carrere. But, without forgetting pure impact tracks like the atomic "Machine Gun" contained in "Wheels of Steel", the album interested in this article is "Strong Arm of the Law", the third album of this quintet from Burnley.
Born with the ultra-vulgar moniker Son of a Bitch, Saxon realized with "Strong Arm of the Law" their most aggressive and faster album of their first period, especially in barbaric songs like the obsessive "Heavy Metal Thunder" and "To Hell and Back Again" and the better structured but furious "20.000 Feet", the most destructive number of the entire album also due to a very punkish riffing...but we mustn't forget that the early Saxon were strongly influenced by Motörhead. All the songs by Saxon are simple, catchy and direct, but also dominated by the tinking screams of Biff Byford, storyteller of rebel lyrics often about the reality (as in the loudmouthed hard blues of "Hungry Years", where rock'n'roll is considered like an instrument useful to fight the rampant unemployment...a very current theme!).
Going now for a while outside the borders of the Great Britain, an honorable mention up to the Frenchies Trust, that, instead, built an entire career on the socio-political reality of their times.
In fact, this fiery quartet from Nanterre is very important for two reasons: firstly, for their big influence exercised on future thrash metal giants like Anthrax; secondly, because Trust were one of the very rare metal bands of those times to widely sing about political themes in according to a so combative left-wing mentality that once they played into the infamous Fleury Mérogis' prison!
The more representative album of Trust is surely "Répression" (CBS), that had also an English version with the lyrics made by Jimmy Pursey, the historic singer of the populist punk band Sham 69. Dedicated to Bon Scott of Ac/Dc, disappeared some months before in 1979 (he was a big friend of the singer Bernie Bonvoisin, so he sang as a guest in the 1979 debut album of Trust), "Répression" has little traces of proto-speed/thrash metal but these ones are more than enough: the conclusive "Les Sectes" (a song about the deranged US preacher Jim Jones, that in 9th November 1978 brought to the mass suicide all the 911 members of his sect into the city of Jonestown, founded by himself to escape from the nuclear holocaust believed imminent by him), so intense and fast throughout its 2 minutes and 40 seconds that it was coverized years later by Anthrax. Coverized by them too is the initial "Antisocial", a true anthem that represent a synthesis of the feisty but dynamic and inventive hard rock of the early Trust. But their songs aren't normal songs: in my opinion, these are speeches dominated by the angry outbursts against the System spewed violently forth by the charismatic Bernie Bonvoisin, a very particular singer that focus his vocal style more on a big expressive force (and on an incredible pair of lungs!) than on the melodies with the result that he is opposed to the shredding of the guitar-hero Norbert "Nono" Krief.
The Danish quartet The Brats was faster and maybe even more unconventional if compared with Trust. The Brats was the pre-Mercyful Fate band in which future known musicians like Hank Shermann and Michael Denner played while their last singer was nothing else than King Diamond! In fact, he was into the line-up of this band before they ceased to exist because their label CBS pretended the comeback of The Brats towards their original punk sound but singing even through their native Language
During their short existence, The Brats released only an album that, simply titled "1980", can be considered as one of the very first attempts to mix hard rock, heavy metal and punk in a single solution, as exemplified perfectly by the fast and well structured "Tame Me (Insomniac)", a song full of Motӧrhead and Iron Maiden influences after an acoustic intro. But unfortunately, I think that the ambitious melting pot created by this band is still bad balanced since the large predominance given to the punk elements starting from the arrogant vocals of the bassplayer Yenz (now in Stormwarrior). Anyway, there are memorable songs like the obsessive and lazy "Complex (Don't Destroy Me)" and the easygoing "Zombie People".
But the synthesis attempted without success by The Brats will be reached completely only through a stoned Walesman and ex-"flower power generation" son along with his two mates: Motӧrhead! Who else?
In fact, "Ace of Spades" (Bronze Records), since its famous titletrack until the devastating "The Hammer" through that supersonic assault known as "Bite the Bullet", is a total onslaught composed of 12 songs and even 5 of them are very fast, and I have to say that these ones are really a lot for a metal album of that time! So, this album is the perfect link between heavy metal, NWOBHM, rock'n'roll and the emerging punk/HC, in order to create a unique and direct sound characterized by the tormented vocals of Lemmy, the contagious rock'n'roll riffing à la Chuck Berry of Fast Eddie Clarke, the wild drumming of a beast like Philty Animal Taylor able to make popular the double kick drum bass, and by a production very dusty so to emphasize at the maximum level the proud street attitude of this trio. This means that, in my opinion, the faster songs of "Ace of Spades" represents really the perfect prototype for the speed metal genre also because they give to the listeners the impression to ride a bike or to drive a car at a breakneck speed, as exemplified especially by the roaring "(We Are) the Road Crew", where you can breathe the smell of the street, a thing that will be typical of fundamentalist speed metal bands like Acid or Warhead, both Belgians.
But the list of speed metal songs could be even longer.
In fact, in 1980 there were many bands that have their own crazy speed metal Anthem and, for this, the NWOBHM movement is exemplary: to name a few, "Sweet Danger" of the dark Angel Witch (a song that was released in 1979 as a single but, considering that it didn't sell like the major label EMi wanted, this one discharged Angel Witch without compliments), the imperious "Metal Man" of the progsters Limelight, "Take Me to Your Leader" of Samson (with a very young Bruce Dickinson), or even the majestic and theatrical "Phantom of the Opera" of Iron Maiden.
In brief, the time was coming for a total radicalization of the '70s hard rock standards, sped up and reinvented in a more energetic and punkier way.