The 1990s saw the emergence in London and some other English cities of a series of highly innovative styles of electronic dance music. Hardcore techno was a fast, linear style deploying abrasive timbres, mainly 'dark' minor tonalities and four-to-the-floor house rhythms, in a distinctively northern European interpretation of the softer and more melodic but equally glacial forms of techno' originating from Detroit producers such as Juan Atkins and Derrick May. Sui generis musical style, a new form, most of whose initial key proponents were black British, made no attempt to imitate Jamaican or American styles of music or dance, marking a very significant break with the history of black British music's dependence upon innovations and canons deriving from those sources. Jungle constituted the first genuinely hybrid musical formation in Britain, its practitioners and aficionados always representing an ethnic cross-section of London's cosmopolitan population, as has remained the case with its various successor genres.