I recall seeing an interview from a shakuhachi master about his approach to playing, and John cage was among the audience. The monk spoke about there only ever being one sound, and playing the shakuhachi helped one realize this. One of the musicians asked what the sound was, and the shakuhachi master clapped his hands and said 'that was it'.

I believe John cage got his inspiration for 4'33 from the komuso tradition, and music students have been joking about it between themselves ever since. But if you actually check out suizen it's a well explored form of meditation.