The knowledge accessible to a given organism can be conceived as a functional linkage of his continuous interaction to the sum of stimulations he receives, sounds being among them. The analysis of this specific knowledge has largely been placed under the rubric of a somewhat poorly defined informational content. But we need to distinguished between a sensorimotor direct treatment (knowing-how) and a properly symbolic descriptive one, that is the issue made of a bunch of shared definitions (knowing-that). The object of this study is to put an exam on the ressources that are offered on both sides by the transfer of analog inscriptions obtained by a sound recorded document. The instrument of observation thus obtained, even if not to seen as transparent, opens up a bridge between qualitative reception and the quantified definition of the signal by the way of a methodic conceptual development
