Chankgeez wrote:Yeah, don't actually do any of this experimenting until you know what you're doing.
I would counter with "you don't actually know anything about this stuff until you do some experimenting". you can read ALL the books and have no ability to translate that into a workable plan of action. being the first to build a new hybrid electro-acoustic instrument or building something that is completely undocumented is %100 dependent on trial and error through working prototypes and partial prototypes. if you have it in your head that a static magnetic field or a DC current/voltage will induce oscillation in a metal spring then I would suggest you prove your idea with a much simpler experiment. I know that the only excitation and therefor the only oscillation will happen when the device is switched on or off. the spring itself has a natural dampening factor due to wind resistance and internal stresses that create heat in the metal. without a guitar pickup, a piezo pickup, a microphone or an electric switch activated by the movement of the spring, there can be no indefinite oscillation of the spring. I would guess that the video you watched had a feedback loop that puts the spring in the loop. keep in mind that noise instrument hackers are sometimes super luck and lazy. a spring can be activated by mechanical, acoustic, electric, or magnetic effects if they are done in a manner that can induce spring vibration. likewise the vibration of the spring in some specific range of motion can be picked up through mechanical, acoustic, electric, or magnetic effects. through the use of transducers and electric AC amplifiers, you can put enough gain in your hybrid feedback loop to have sustained oscillation for an arbitrary length of time controlled by the user/musician/operator. pitch is usually very easy to manipulate by changing any variable in the experiment. the range and control may not be what you are looking for so you will eventually need to be some kind of scientist to make anything more than a cheap trick.