This ethnography, titled "Centro del Margen" (Center of the Margin), presents a journal chronicle of a day spent in an underground or clandestine rap music recording studio located in a marginal low income neighborhood of Buenos Aires. This article uses rap, the music produced at El Triángulo Estudio, to build a lens from which to narrate the racial, economic, social and geographic conditions of an emergent sector of Argentina's pop culture. Centro del Margen identifies the processes of place making and community building that occur at El Triángulo Estudio and proposes the term lumpen-innovator to describe the self-taught engineers, songwriters, and producers who are born from processes of communal creativity under conditions of economic scarcity. By using a chronicle or diary writing style with a subjective narrative that replaces an omnipresent voice that can cause generalizations, the essay experiments with textual representation and aims to empower its protagonists as active agents in the creation of the ethnographic present. Centro del Margen identifies a growing sector of organic intellectuals who are successfully circumnavigating institutionalized protocols of the culture industries, while it also aims to explain why rap music, a genre that has been popularized throughout Latin America for more than a decade, is only now becoming widespread among Argentine youth. Potential factors include the association of rap music with Afro-diasporic sounds combined with a low demographic of Afro-Argentine populations, the repercussions from the national 2001 economic crisis that limited access to electro-musical production technology, and the musical influences of a generation marked as the "grandchildren of the disappeared" that were raised on Spanish rock. [ABSTRACT FROM AUTHOR]