According to the good people at the Smithsonian's National Museum of American History, April is Jazz Appreciation Month. With this in mind, we'll attempt to name nine great jazz soloists you might want to check out, especially if you're curious about jazz but don't know where to start with your listening. When a musician, while playing a composed piece of music, chooses to imaginatively make up original music that complements the composition's melody, chords, and rhythms, what they're doing is "