Hi. can someone explain how when sending a signal of various frequencies to a speaker , how is it possible for the magnet to resonate at more than one frequency simultaneously??

 

Resonance has nothing to do with it. It is responding to the magnetic field created by the current that is a reproduction of the waveforms feed into the speaker.

The waveforms are complex, and contain many frequencies. But the waveform is also reproduced by the movement of the speaker.

 

Okay, I guess what I don't understand is how the movement of the magnet translates into several sounds, ie we can hear a guitar and drums simultaneously ?

 

Hello,

The sounds are added as a current.
The cone (diaphragm) will move according to that current.

http://www.12vhifi.nl/pix/speaker-working.swf

This is a link from the EDUCYPEDIA page on loudspeakers:
http://www.educypedia.be/electronics/loudspeakers.htm

Bertus

 

Well, what's a "frequency"? An oscillation. You can have many oscillations superimposed, or put another way; you can have a signal consisting of multiple frequencies.

Take a sheet of paper and add sin(x) and sin(2x) together for example, what you get is a signal consisting of two frequencies. You won't necessarily "see" the seperate oscillations in the final signal anymore - what you get in Music is these "chaotic" waveforms seen in a signal analyzer.

Back to the two sines - the speaker will (ideally) move in the same way as the final signal. What you hear then is (ideally) two oscillations with the given frequency.

Clear?

 

Exactly what Flow said. Your question has the same answer as these: How can I hear music from a simple overlay of sine waves of various frequencies? How can the computer represent the music I hear into one curly, weird looking line?
The answer is, you don't have to see, hear, or generate the separate sines to get the final result. The signal wich contains them allotgether carries all the information that composes the sound.

 

Awesome guys thanks a lot

 

In a nutshell, it's the principle of linearity and superposition.