First Steps
What exactly are Open Ears, anyway?
Simply put, ears that don't discriminate and consider every sound, be it intentionally musical or not, as valid and worthy of attention. It's possible to get as much sonic enjoyment out of a freight train going by (best to be right next to it if possible, btw) as it is Mahler's Fourth Symphony or the new Sonic Youth album (though "goo" is still better).
Open Ears allow us to stay open to different styles of music and learn as much from them as possible. Even if you're a diehard metallica freak and can play all their songs note-for-note, there's still something you can learn from Albert Lee (check out "speechless"). Or if you ONLY play classical guitar, I bet you can get some ideas and inspiration from Elizabeth Cotten, Kaki King, or Charlie Hunter. Why? Because everyone is dealing with basically the same equipment: six strings and ten fingers. Hearing an entirely different approach to the instrument is not only inspiring, it can be liberating!
I have five volumes of listening CDs with questions I've compiled for this very purpose and am pretty sure that even though the response may be "that was really weird," some ears have definitely been opened!