Foundation sounds before the famous three

Metro Downbeat was a London sound system founded in the late 1950s by Jamaican-born electrician Percival 'Metro' Miller, who named it in direct tribute to Sir Coxsone's Downbeat in Jamaica. One of the first Jamaican-style sound systems to operate in Britain, it wound down as a touring dance sound after Miller was injured in a 1969 altercation.

Sir George was a London reggae sound system based in Clapton, noted for a long-running residency at Cubies in Dalston Junction. Rather than the roots reggae favoured by many contemporaries, it specialised in lovers rock for a new generation of London-born Caribbean youth, with musician Anthony Brightly (formerly of the band Black Slate) helping build its reputation.

Lord Koos (Egerton Koo, who came to Kingston from Guys Hill around 1944) built one of the leading early-1950s Kingston sound systems, Lord Koos the Universe, buying stock from Randy's record shop. By the mid-1950s it was strong enough to 'blow' top rivals including Sir Coxsone's Downbeat, Duke Reid the Trojan and King Edwards the Giant.

First-generation Kingston sound system of the early 1950s, named in histories alongside Tom the Great Sebastian and Sir Nick the Champ; it played US rhythm and blues on the downtown lawn circuit, and Bunny Lee recalled it later amalgamating with Coxsone's Downbeat.

Sir Nick the Champ was among the operators of the earliest Kingston sound-system era, playing American R&B at dances alongside contemporaries such as Count Smith the Blues Blaster and Lord Koos as the culture grew from house parties into large street dances in the 1950s. He is remembered as part of the pioneer generation that preceded the 'Big Three'.

King Edwards the Giant was a powerhouse Kingston sound system built by brothers Vincent and George Edwards, active roughly 1955-1967 and counted with Coxsone's Downbeat and Duke Reid the Trojan among the 'Big Three' of the foundation era. Known for imported R&B and fierce sound clashes, its associated record shop drew aspiring musicians including a young Bob Marley and Jimmy Cliff.

Clement "Coxsone" Dodd's sound system, a dominant force in 1950s and 1960s dances and a seedbed for the Studio One label.

V-Rocket (V. Rocket International) is a long-running reggae sound system founded by Jamaican migrants Dougie and Imogen Robinson, who came from Spanish Town to the UK in the 1960s and built the sound within Britain's blues-party scene, later based in Nottingham. Active for roughly six decades, it is regarded as one of the UK's pioneering sounds and is fronted in later years by selector Lady V, and was the subject of a documentary on its sound-system dynasty.

Jamaican audio engineer, musician, inventor and trade unionist (1917-2017) whose 1947 hand-built high-fidelity amplifier, made to play records outside his Bop City shop in Kingston, became the template for the sound system; he supplied amplifiers to Tom Wong, Duke Reid and Coxsone Dodd, built an early solid-body electric guitar, and received the Gold Musgrave Medal in 2011.

Percival 'Metro' Miller (born 1941 in Jamaica) emigrated to Britain in 1957 and became one of the pioneering operators of Jamaican-style sound systems in London, running Metro Downbeat. After his own sound wound down following a dancehall injury in 1969, he built amplifiers full-time, most notably constructing the valve amplifier rig behind Jah Shaka's sound.

How fenced yards, imported 78s and crowned sound men turned 1950s Kingston dances into an industry.

How a Jamaican teenager carried the logic of the dancehall sound system into a South Bronx rec room and helped set hip-hop in motion.

In 1950s Kingston, Coxsone Dodd's Downbeat and Duke Reid's Trojan turned rival dances into the foundation of an entire music industry.

Before there were selectors and deejays, there was the amplifier, and the men who built it.