You can notice the compression at the edges of the audio, like vocals or cymbals. Linda Ronstadt is one singer who's voice makes compression obvious - her line turns into a hacksaw blade on some songs.

That said, every system has distortion - the question is what sound do you like/want. Do you want a sound that's more forward or more laid back? Do you like more midrange? Vocals?

Audio also becomes more complicated because of hearing loss. I can't hear anything over 12-13k, so I'm sure that's affected my audio setup at some level.