Originally referring to a "dub plate" acetate disc containing an alternative or remixed version of a song, dub developed into a distinctive style of primarily instrumental reggae in the early 1970s. Producers would use the B-side of a single to experiment with techniques and styles unsuitable for the A-side, and later these versions/dubs would be compiled into dub albums, and/or reused by singers and Deejays. Early pioneers included producers Lee "Scratch" Perry, King Tubby and Keith Hudson. The genre is characterised by emphasis on the rhythm track, extensive use of sound effects and heavy reverb. While Jamaican dub LPs became rarer after the early 1980s, the style has been highly influential in the development of electronic music by developing the modern concept of remix and forming the roots of Dancehall, while the sound and name has passed on to such genres as Dub Techno, Ambient Dub and Dubstep.