These performances are completely improvised and unrehearsed.
The results are truely unique -- some improvisations are like songs in the sense that they have a melody and some song structure. Some songs are more experimental, meandering, and off the wall.
Due to the nature of improvised performance, occasionally a wrong note is played. Remember, none of the music on the CD was rehearsed or practiced prior to the performance, so mistakes occasionally happen. Rather than edit out those mistakes, they were left in the recording for the sake of honesty. It also creates a much more intimate, "real" sound, as opposed to a polished, perfect studio performance.
Due to the nature of improvised music, one never knows what one will end up with.
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