I had a vivid illustration of the relationship between "listening to sound as sound" and "listening to sound as music."
I was testing ERS paper on my headphone cable, listening to a string quartet. I was "conducting" along to get a strong feeling for the rhythm and expressive shaping of the musicians. At one point, half of the instruments enter "off the beat" (in a syncopated rhythm) and there is a wonderful feeling of getting lost---losing a strong feeling of downbeat for a few moments. It's expressive, and inspired me to change how I was moving my hands.
Cue next experiment. No ERS paper. I was listening to aspects of the sound---it seemed a bit more airy but perhaps more gritty too--- when that same passage occurred. But I hardly noticed the music---I was intent on the sound.
A moment later it hit me that this passage was missing the effect. So I replayed it, this time "dancing" my hands to connect with the rhythm. And there was no "getting lost" effect. Every event was perceived as precise in time.
I put the ERS paper back and cued the passage. This time the "getting lost" effect was strong. By shifting my attention to the sound, I discovered that the effect originated within the first violin, which played quietly and slightly out of sync with the other players. The difference in terms of the sound was a slight improvement of delineation of inner detail. Really very slight. But in terms of the music the difference was large. The musical effect happened strongly vs. not even noticeable!