Visual v Musical Obscenity

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so, i grew up in Mapplethorpe-trial/Larry-Flynt-era Cincinnati. visual obscenity was like my hometown’s “thing.” maybe that’s the reason i’ve never really found it that interesting, philosophically. porn is always an interesting issue to teach in feminist philosophy or gender & aesthetics, but, i dunno, i personally as a scholar just can’t get “into” it.
but today i was thinking about the differences between visual obscenity—usually naked bodies and/or blasphemy (e.g., piss christ)—and musical obscenity. it seems like there are two levels of musical obscenity: (a) the verbal content of the lyrics, and (b) the affective content/form of the musical work/performance itself. this latter type of obscenity is interesting b/c it’s not tied to the representation of a taboo idea, concept, or symbol. it’s about transgressive affective or phenomenological states. even the ancient greeks tied musical experience (performance & listening) to ethical practices, i.e., to technologies of the self. 
and i think, especially in the US, these affective states are deeply racialized. so, if what is considered visual/verbal obscenity generally references sex (and violence, and blasphemy, and drugs, but mainly sex), maybe non-lyrical musical obscenity generally references racial transgressions? just think about the history of black pop music in the US. first, it was literally segregated in record stores, cordoned off in “race music” sections. music was the first broadcast mass medium. white kids could listen to “black” music; music—as electrical currents—could transgress social and political segregation. this, after all, is the subtext of John Waters’s Hairspray. music was a gateway to racially transgressive corporeal practices and affective states.
So: Is there a kind of musical obscenity that works/functions differently than visual obscenity? Is musical obscenity, at least in postwar US (and maybe UK) pop culture, tied to race in a way that visual obscenity is not? Is racial transgression what makes some sonic experiences feel “obscene”?
I dunno. These are all open questions. I hope somebody has written about this—and  if you know of any good work on this & related issues, I’d be eternally grateful for your suggestions.