ðə stˈeɪʃən wʌz ˈoʊnd baɪ ðə ɹˈæntʃoʊ kjˈuːkɐmˌɑːŋɡə kwˈeɪks bˈeɪsbɔːl tˈiːm ænd ɪts kˈɔːl sˈaɪn wʌz dᵻɹˈaɪvd fɹʌm "mˈʌsəl," ɐ tˈɜːm ɐsˈoʊsɪˌeɪɾᵻd wɪððə stˌɛɹɪoʊtˈɪpɪkəl stɹˈɛŋθ ʌv ˈæθliːts.
The station was owned by the Rancho Cucamonga Quakes baseball team and its call sign was derived from "muscle," a term associated with the stereotypical strength of athletes.