Vibrate a string with electricity? Best ways?

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Vibrating a string with electricity is feasible using an electro-magnet, which should be pulsed at the string's fundamental resonant frequency for optimal results. The electro-magnet must create a changing magnetic field, which can be achieved with oscillating current, not necessarily at resonant frequency. The placement of the electro-magnet is crucial for efficiency, though specific guidelines are not widely available. Devices like the EBow demonstrate practical applications of this concept. Overall, varying the electromagnetic field effectively excites the string to produce vibrations.
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Is it possible to vibrate a string with electricity? I'm guessing an electro-magnet placed close to the string would be able to vibrate it.

If the electro-magnet is used to vibrate the string, I'm guessing the electro-magnet should be pulsed at the fundamental resonate frequency of the string? Maybe different frequencies or harmonic intervals are more efficient? And I wonder should the electro-magnet be fed a sine-wave or is some other wave more appropriate to excite the string?

Also is there anything that would tell me where the most efficient placement of the electro-magnet would be?
 
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As far as I know, an electromagnet will do nothing to string. Absolutely nothing, unless you physically hit the string with the electromagnet.
 
UncertaintyAjay said:
As far as I know, an electromagnet will do nothing to string. Absolutely nothing, unless you physically hit the string with the electromagnet.

Here's a project where electro-magnets are used to actuate strings on a piano.

http://music.ece.drexel.edu/research/mrp/actuation

Unfortunately I haven't been able to find much else on the internets.
 
Ohhhh, you're talking about metallic strings, I was thinking of the rope thingies. In that case yeah. But you have to vary the field of the electromagnet. Doesn't have to be resonant frequency though. As long as you have a changing magnetic field, you'll move the wire. So, if your current to the electromagnet oscillates( like a.c , which is sinusoidal, but it doesn't have to be), the string will vibrate
 
MauriceWaves said:
Is it possible to vibrate a string with electricity? I'm guessing an electro-magnet placed close to the string would be able to vibrate it.

An EBow is one such device:

https://en.wikipedia.org/wiki/EBow

I used one a few years ago, great fun.
 
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