The term "audio sequencer" or "audio sequencing" seems to be not clearly defined (not defined on wikitionary), because it is relatively new expression.
- Music sequencer – A class of device or music software to record, edit, and play back the music, by handling musical notes and performance information in various forms.
Several peoples tend to use the term "audio sequencer" to refer several kind of "music sequencer".
However, their definition seems unclear.