An imaginary dialogue between an ethnologist and an ethnomusicologist introduces readers to a debate about the underpinnings of activities in ethnomusicology and the latter's place among the human sciences. Can ethnomusicology be considered to be a full-fledged discipline ? Or should we see it as needing bridges toward other fields ? If so, which bridges, and under what conditions ? This attempt to answer these questions focuses on the music of a Gbaya group (Central African Republic). This music provides essential information for understanding the contacts and relations that the Gbaya have maintained over time with their neighbours. This example serves to defend ideas about the originality and independence of ethnomusicology.