In the early 1980s, a commercial form of jazz fusion called "pop fusion" or "smooth jazz" became successful, garnering significant radio airplay in "quiet storm" time slots at radio stations in urban markets across the U.S. This helped to establish or bolster the careers of vocalists including Al Jarreau, Anita Baker, Chaka Khan, and Sade, as well as saxophonists including Grover Washington Jr., Kenny G, Kirk Whalum, Boney James, and David Sanborn. In general, smooth jazz is downtempo (the most widely played tracks are of 90–105 beats per minute), and has a lead melody-playing instrument (saxophone, especially soprano and tenor, and legato electric guitar are popular).