When I think about music as a body of work, I think first of the Cortland Street J&R. I remember being 12 years old, standing on a raised landing and gazing over a hall of jewel cases. Due to the recent proliferation of streaming sites, the cavernous music store isn’t an apt description of the music world anymore. A year and a half ago, the Manhattan J&R closed and, long before that, my memory of it faded. In retrospect, I don’t think the store even had a raised landing.