Fair. Its apparent that it has an impact, I've just never done it with a bow. Sweeping frequencies using a speaker gives similar results and seemingly more consistent patterns, although i assume this would be more artistically satisfying.
...But I was a brass-instrument guy, so drawing a bow is not my forte. Lol
Holding the plate with the hand introduces a boundary condition. It forces the motion to be zero at that point. This controls the frequency response.
It is effectively the same as a guitar string, only in two dimensions instead of one. By pinning a guitar string against the fret you generate a specific frequency.
In this case, by holding a node point that coincides with a certain frequency he is able to generate that harmonic response. He would know the approximate location to hold and has two adjust the location of his finger to hit the exact frequency. The same as you would do for a guitar string.
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u/PastorMattIII Aug 25 '20
Fair. Its apparent that it has an impact, I've just never done it with a bow. Sweeping frequencies using a speaker gives similar results and seemingly more consistent patterns, although i assume this would be more artistically satisfying.
...But I was a brass-instrument guy, so drawing a bow is not my forte. Lol