Instruct: Classify Amazon reviews into positive or negative sentiment
Query: One of the best vocalists you never heard

I discovered Roland Kaiser's music while stationed in Germany in the mid-80's. I had caught "Joana" on Radio Bremen Eins, and was able to ascertain, through my limited Deutsch, what it was and who sang it. The 45 ended up in my collection rather quickly. After finding some of his albums on CD, I must say this particular CD offers the best of many of them. Best tracks are "Joana", "Santa Maria", and his vocal cover of "Verde", titled "Frei, das heisst allein". Give it a listen. You'll be hooked.