A friend gave me a CD by Bella Flect and The Flectones. I had never heard of them until now and I was knocked out hearing electric banjo and the complete mastery of the group. That got me thinking about unique sounds that leave a lasting impression. The first time I heard Paul Butterfield play amplified harp I thought that was the ultimate. The same with Ravi Shankar live at Monterrey. Michael hit it out of the park with his composition East West. Jimmy Hendrix created something totally new as did the Beatles with Sargent Pepper. Excellence in musicianship as demonstrated on a particular instrument is one component, but the composition can transport you on a musical odyssey to really new worlds.
I welcome your recommendations and experiences, this would be great to share.