Thrash Metal (sometimes referred to simply as Thrash) is a subgenre of Heavy Metal music. Thrash is at the more Extreme Metal end of the Heavy Metal spectrum and can be characterised by high speed and aggressive Guitar riffs, that also feature fast, percussive and low-register sounds, overlaid with shredding-style lead work. Thrash metal lyrics also often deal with social issues using visceral and blunt language, an approach which partially overlaps with the hardcore genre. A lot of times the vocals are clean cut. The “Big Four” are easy examples and very good examples of the genre, they are Slayer, Megadeth, Metallica, and Anthrax, these are the 4 that simultaneously created and popularised the genre in the early 1980s.
The origins of thrash metal are generally traced to the late 1970s and early 1980s, when a number of bands began incorporating the sound of the New Wave of British Heavy Metal, and the attitude of the punk movement, thus creating a new genre and developing into a separate movement from Punk, Rock and Hardcore. This genre is much more aggressive compared to the genre that's often thought of as its relative, Speed Metal, which would generally be a lot more "technical".
Thrash metal features a number of fast and rapid tempos, low-register, quick, complex guitar riffs, high-register guitar solos, and aggressive vocals. Thrash rhythm guitar playing is characterised by "palm muting" and "staccato" with a heavily distorted tone and tightly controlled riffs to create a “chugging” sound.
Thrash guitar solos are almost exclusively played at high speed, as they are usually characterised by "shredding", and use techniques such as "sweep picking", "legato phrasing", "alternate picking", "string skipping", and "two-hand tapping". Thrash lead guitarists are rooted in the New Wave of British Heavy Metal movement. Frantic bass drum use is also common. Thrash drummers often use two bass drums. Some thrash drummers are revered as some of the “best drummers in rock”.
Due to the genre’s high speed, many thrash bassists use a pick to keep up with the other instruments. However, some prominent bassists within thrash used their fingers, including Frank Bello, Greg Christian and Cliff Burton. Several bassists use an overdriven or distorted bass tone, an approach popularised by Burton and Lemmy of Motörhead.
Some Thrash Bands
Not everyone will always agree on what's Thrash and what's not, but this list had a number of artists that would fit into that bracket, as well as probably some others;-
Flotsam and Jetsam
Stormtroopers of Death
Vision of Disorder