Your comparison to IPA is interesting—it’s as if the piano roll is a raw “phonetic” transcription, while traditional notation is more like a structural “phonemi

Your comparison to IPA is interesting—it’s as if the piano roll is a raw “phonetic” transcription, while traditional notation is more like a structural “phonemic” representation that conveys the sounds as they’re functionally understood. The former treats all information as equally important, missing high-level structure and using space poorly; the latter omits some information and encodes other information redundantly or in a compressed format to convey what’s most important to the reader.