It is impossible to overemphasize the importance of sound systems to the development of reggae music, as just about every record producer, singer and DJ from the 50s onwards has been closely involved with them in one way or another. They were the forerunners of today's mobile disco, but the amount and weight of their amplification equipment ensured the sound of the music could be felt as strongly as it was heard. In the 50s, R&B radio stations from southern American cities beamed their music to a responsive Jamaican audience, and the popularity of R&B prompted enterprising locals to start their own sound systems. Operators such as Coxsone Dodd ("Sir Coxsone The Down Beat") and Duke Reid ("The Trojan") became stars in Jamaica on the strength of their sounds - both for the records that they played and for the way in which they presented them. The top outfits would play in competition against each other and the rivalry was frequently violent and bloody. Records were hunted out in the USA where vast amounts of money were spent on the right tunes - the label details would then be scratched out to stop their rivals discovering the identities of these top tunes.
The sound system operators started to make their own R&B-based recordings as the supply of hard R&B records began to dry up in the late 50s, and the black American audiences moved towards a smoother style of music, which failed to spark the interest of the Jamaican audiences. At first, these recordings were intended solely for exclusive use (on acetate disc or dub plate) by the sound that made them, but they proved so popular that the top "sounds" began to release these records, and ska and the Jamaican recording industry were born. From this point onwards, the development of Jamaican music through ska, rocksteady, reggae, rockers, dub, dancehall and ragga was inextricably linked with sound systems, both as the testing ground for new records, but, more importantly, for singers and DJs to test out the crowd's response as they took their turns at the microphone. Their popularity prompted the proliferation of sound systems in New York, London and Toronto - at first, anywhere with an expatriate Jamaican community - but later, their influence spread in more diverse directions; the importance of Jamaican Sounds to the development of hip-hop and rap in America, for instance, has yet to be fully credited. The Sounds have gone through as many changes in styles and fashion as reggae music and have become a cultural rallying point across the globe. The current fashion is for playing "specials" - one-off acetate discs recorded exclusively by current big names, extolling the virtues of the particular sound for which the "special" has been voiced, usually to the tune and rhythm of a popular "commercial' hit record. DJs" live contributions are kept to a minimum where once they dominated the sound. In many ways, the wheel has turned full circle, but to hear a top sound system playing out either in the warmth of a Kingston open-air dance or crowded together in a small club in London or New York is to understand fully the strength and power of Jamaican music, and to experience its direct and very real influence on its own committed following.