This is a little experiment I did lately, inspired by the luminist garden project: http://folktek.com/instruments/electrocoustic/luminist-garden
DIY ambient machine is amplified by two piezoelectric sensors inside the wood box (no power supply needed). I’ve used old bass strings and springs. Also I’ve added a button to stop the sound and volume pot.
Teenage Engineering OP-1 is just used to add some effects.
My music: https://soundcloud.com/orioldomingo