Just some observations.
PDF page content that is an image (and music notes may very well be that in a given PDF) then all that can be exported is the image.
Only an image editor can "edit" such eh.
As to textual content - once in TXT, RTF, DOC or DOCX yes, expect to have to do "cleanup"
Of course there's the old school alternative that is always available.
Paper copy beside you as you transcribe to a fresh word processing file.
Be well...