Historic recordings of Neuhaus' interpretations of John Cage's Fontana Mix made with a pair of tympani with contact microphones attached, speakers adjacent and controlled feedback operated by Neuhaus at a nearby mixer. Important because it is a very early example of live electronic music, because it a very early use of controlled feedback (outside rock) and because it was evidently LOUD. The sleeve notes are good and well illustrated. You are recommended to listen with the speakers as loud as you can bear. I find it more interesting than good to listen to (I find it rather irritating). Though many will disagree (feedback is popular again now). Historic.