Technically, the opposite of a keyboard would most likely be an unpitched percussion instrument because technically a keyboard is in the percussion family as well. So it should be like a snare drum or maybe a bass drum.
Great site, but your sound citation is not from Einstein on the Beach, the counting is though. Your first indication should of been the fact that the music in that opera is entirely minimalistic. Also, c*cks.
umm, thats not minmalism but ok. if you knew anything minimalism is a style of 20th century music. So the music should have been by Philip Glass or Steve Reich
