Is there one who was hearing to be found here? Or is there merely hearing?
This meditation uses the "sense door" of hearing, or "sense consciousness", to point out that there is no subject, not Self that does the hearing.
It also points out the single boundaryless and unstructured space of awareness in which this hearing/ listening occurs at a single place.
There is no listening object "out there". it is all happening in consciousness / awareness / mind.