Recently I found this video showing the "visual representation" of sound waves.
I was trying to figure out how these shapes were being generated. I am interested in the parts where there is a stable shape.
At this point in the video they reference a perfect fifth - based on this diagram a perfect 5th (7 semitones) would make a ratio of 3:2
I was able to generate this same image by plotting the following functions on desmos
So far for two different tones at once, everything is making sense since I can map one part of the ratio to the y axis and the other part to the x axis.
For one more example at this point, they are making a major triad, and so for first part of that, I was able to use the ratio 5:4, which generates this (almost the same as the video but upside down)
But then they add in the 3rd note. Now I have no idea what they are drawing. Initially I thought they might have been combining the two ratios into one.
- That is the major 3rd is a 5:4 in relation to C, the perfect 5th is in 3:2 (6:4) in relation to C, therefore their sum would be 5:6 in relation to C (not sure if that's true, just an idea I had), but drawing that ratio didn't give the same result they have in the video...
- The closest I've gotten to what they have is by summing more of the trigonometric functions together (I was trying things out and this looks the closest):
- Could someone help identify how they are animating more than 2 tones together?
- Why do the visualizations still have slight movement to them even though they are in just intonation?