This is a definition of the orchestra field as used in track meta data.
- if the orquestra has an orchestra name, use that e.g. Quinteto Pirincho, Colortango, Orq. tipica Victor, else
- if the orchestra is known by the leader, use that
- e.g. Francisco Canaro
- if a director is identified, use his name.
- e.g. Armando Cupo.
- if any other orchestra identification is available, use that, else
- if any instrumentalists identification is available, use that, else
- if no instruments play on the track, use "-", else
- use "?".