By the late 1970s, AOR radio discarded the wide range of genres embraced earlier on to focus on a more narrowly defined rock sound. The occasional folk, jazz, and blues selections became rarer and most black artists were effectively eliminated from airplay. Whereas earlier soul, funk, and R&B artists like Stevie Wonder, War, Sly Stone and others had been championed by the format, AOR was no longer representing these styles, and took a stance against disco. In 1979, Steve Dahl of WLUP in Chicago destroyed disco records on his radio show, culminating in the notorious Disco Demolition Night at Comiskey Park.