Recently, I had the privilege to see a unique performance of Alban Berg's Chamber Concerto by members of the Chicago Symphony Orchestra, lead by Pierre Boulez, with Daniel Barenboim on piano and Pinchas Zukerman on violin. This concert was special because it re-created a landmark recording of this work by the same ensemble. The other unique thing about this concert: the musical work is only about 30 minutes long, but it was the only piece of the evening. Mr. Boulez and the entire ensemble came out and discussed the work (with examples) for 1 hour, 40 minutes, then took a short intermission, then played the work.
What makes this music so interesting that you can talk about it for 3 times as long as the piece itself? Well, it would take me over an hour to explain! Here are some examples, though. This piece was written in homage to Berg's teacher, Arnold Schonberg, who developed the 12-tone method of composition. The first theme of Berg's work represents Schonberg, Berg, and Anton Webern (another student) with the motif Arnold Schonberg Anton Webern Alban Berg (using the German alphabet). So, the main theme of the work uses the names of the teacher and students. Another example: the second movement is a palindrome: it plays up to the middle (signified by the piano's only involvement in the 2nd movement) the plays in reverse to the end, using different combinations of instruments so that it's not immediately obvious. There are lots of mathematical features in this music: the first two movements have 240 bars each, and the third has 480 bars.
Needless to say, this is a fascinating piece of music, made all the richer if you understand the context of the time in which it was written and all the ideas that went into it. Many people who don't like modern serious music don't have the correct expectations or context. Just as the movie Memento is different than Casablanca, they are both great achievements. The same is true for serious music.