Sustained listening

I am endlessly fascinated by the musical direction sostenuto. I know well its meaning for the performer: Slow down and play notes in a cantabile manner prolonged beyond their normal time value. However, because I subscribe to a collaborative view of music making that includes the audience, I believe that directions are also addressed to the persons who are involved in the creation of a piece through their active, disciplined listening.

Thus I wonder, in such an expansive understanding of sostenuto, what is to be sustained – lingering or stretching? duration or repetition? accompaniment or mood? support or sustenance? stasis or style? tempo or texture? tension or temperament? Listening for sustainability to more than two centuries of this mode in the examples below, from Beethoven’s intimate (1801) to Norman’s grand piece (2018), may clarify or amplify these possibilities.