mˈæsi ɪz ɹᵻnˈaʊnd fɔːɹ hɜː mˌʌltɪfˈæsɪɾᵻd pɹədˈʌkʃən slˈæʃ mˈɪksɪŋ ænd ˌɛndʒɪnˈɪɹɪŋ skˈɪlz, wɪð hɜː fˈɜːst mˈeɪdʒɚ bɹˈeɪkθɹuː əkˈɜːɹɪŋ wɪð nˈaɪntiːnhˈʌndɹɪd nˈaɪnti θɹˈiː ˌʌndɚtˈoʊ, ðə fˈʊllˈɛŋθ tɹˈɪpəl plˈætɪnəmsˈɛlɪŋ deɪbjˈuː fɔːɹ lˌɑːs ˈændʒəlɪs ɔːltˈɜːnətˌɪv mˈɛɾəl bˈænd tˈuːl æz wˈɛl æz hɜː wˈɜːk wɪð sˈɪstəm əvə dˈaʊn, dʒˈɑːni kˈæʃ, ɹˈɛd hˈɑːt tʃˈɪli pˈɛpɚz, ænd bɹæzˈɪliən bˈænd sˈaʊθ kɹˈaɪ.
Massy is renowned for her multifaceted production/mixing and engineering skills, with her first major breakthrough occurring with 1993's Undertow, the full-length triple platinum-selling debut for Los Angeles alternative metal band Tool as well as her work with System of a Down, Johnny Cash, Red Hot Chili Peppers, and Brazilian band South Cry.