I've written on this before and probably will again. Looking through someone else's eyes, or hearing through someone else's ears is a great learning experience.
Terri and I have been trying to pick out carpet for the home theater we're building. It's tough for both of us, me in particular. You look at small pieces and try to envision them in the room as best you can. When a third party takes a look and offers their opinion, all of a sudden you see your choices in a whole new light.
The same is true for audio. I can listen to a track multiple times and play it for someone else and hear it anew. The listener points out something I hadn't heard, notices something I haven't noticed and it becomes a new experience.
I think audible and visual objects are so complex our senses can only record a small bit of them. When someone else points out a different slice of what they see or hear, we can then add that to our consciousness.