Because the killer, Mrs. Voorhees, appears onscreen only during the final scenes of the film, Manfredini had the job of creating a score that would represent the killer in her absence. Manfredini borrows from the 1975 film "Jaws", where the shark is likewise not seen for the majority of the film but the motif created by John Williams cued the audience to the shark's invisible menace. Sean S. Cunningham sought a chorus, but the budget would not allow it. While listening to a Krzysztof Penderecki piece of music, which contained a chorus with "striking pronunciations", Manfredini was inspired to recreate a similar sound. He came up with the sound "ki ki ki, ma ma ma" from the final reel when Mrs. Voorhees arrives and is reciting "Kill her, mommy!" The "ki" comes from "kill", and the "ma" from "mommy". To achieve the unique sound he wanted for the film, Manfredini spoke the two words "harshly, distinctly and rhythmically into a microphone" and ran them into an echo reverberation machine. Manfredini finished the original score after a couple of weeks, and then recorded the score in a friend's basement. Victor Miller and assistant editor Jay Keuper have commented on how memorable the music is, with Keuper describing it as "iconographic". Manfredini says, "Everybody thinks it's cha, cha, cha. I'm like, 'Cha, cha, cha? What are you talking about?'"