SkruntSkrunt
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Youtube: Skruntskrunt - Left 4.5k Piezo Ceramic Right Homegrown Crystal With Toothbrush

Here is a demo of the big crystal with the tinfoil on the right channel and a 4.5k piezo contact mic on the left channel. There’s a toothbrush involved as well.

Description: http://skruntskrunt.ca/blog/2012/09/19/playing-with-piezo-crystals/

Home made piezo crystals + homemade amp and dehummer used to make noise.

Audio file: http://skruntskrunt.ca/a/skruntskrunt-left-4.5k-piezo-ceramic-right-homegrown-crystal-toothbrush.ogg

Source code: https://github.com/abramhindle/visualize-audio-with-images

https://youtube.com/watch?v=tSS3xVvSGtk