DJs such as Grand Wizzard Theodore, Grandmaster Flash, and Jazzy Jay refined and developed the use of breakbeats, including cutting and scratching. The approach used by Herc was soon widely copied, and by the late 1970s, DJs were releasing 12-inch records where they would rap to the beat. Influential tunes included Fatback Band's "King Tim III (Personality Jock)," The Sugarhill Gang's "Rapper's Delight," and Kurtis Blow's "Christmas Rappin'," all released in 1979. Herc and other DJs would connect their equipment to power lines and perform at venues such as public basketball courts and at 1520 Sedgwick Avenue, Bronx, New York, now officially a historic building. The equipment consisted of numerous speakers, turntables, and one or more microphones. By using this technique, DJs could create a variety of music, but according to "Rap Attack" by David Toop "At its worst the technique could turn the night into one endless and inevitably boring song". KC The Prince of Soul, a rapper-lyricist with Pete DJ Jones, is often credited with being the first rap lyricist to call himself an "MC."