Milton Babbitt, Semi-simple variations (1956)

Here is a recording of Milton Babbitt's Semi-simple variations for piano:


Questions:

1. Describe your general aural impression of the piece. Is it organized? Chaotic? Melodic?
   
2. What is being varied in this piece? How does Babbitt vary these elements?
   
3. How many variations do you hear?
   
4. What might Babbitt have meant by "semi-simple?"
   
5. Compare this with other sets of variations for piano that you might know (see, for example, Webern's piano variations, which had a big influence on Babbitt)
   
6. Could you determine whether or not this piece was improvised or strictly organized based solely on listening to it?
   

Additional resources:

• Those Who Dig take an approach not unlike mine (n.b. I found this site after putting this post together)
  
• A jazz arrangement (with choreography!) by The Bad Plus: