1. Musicologists who certainly can be included in the new materialist generation are:
The most explicit and as far as I know only case of fieldwork-new materialist-musicology is Milla Tiainen's "Corporeal Voices, Sexual Differentiations: New Materialist Perspectives on Music, Singing and Subjectivity" (2007). (Abstract here, if you don't have full-text access through your library contact me).
Looking back in time, we see that the famous 94 essays on mind/body and on lesbian musicology of Suzanne Cusick are groundbreaking new materialisms at full force.