To put it very basically, your earphone includes a piece of plastic that vibrates in accordance to those indicators received out of your player it is connected to. The plastic vibrates due to the metal coil that’s attached to the magnet, that allows the plastic to create the noise waves that play into your ear.

That is it, actually. It seems easy enough, but I could not have considered it.

Jezen Thomas at eHow.com offers a added comprehensive explanation to us, he states that,

“Earphones consist of a speaker cone, an iron coil, a magnet and speaker cables. When earphones are plugged into a music-playing device like a stereo, electricity is sent along the speaker cables. The speaker cables feed this electrical current through the iron coil, which behaves as an electromagnet. The coil then attracts or repels the permanent magnet, depending on the electrical current sent by the music-playing device. This causes the coil to move, which subsequently pushes and pulls the speaker cone. As the speaker cone vibrates as a result of this movement, it creates sonic waves that resonate through the air and are transferred through small bones and membranes inside your ear”.

Evidently, you can find several types of earpieces, but all in all, that’s it.

Some earpieces, however, do feature other features. Noise canceling earpieces, as an example, can generate a tiny field of white noise round the amp itself, that acts as something of a vacuum and has the consequence of disabling exterior sound. These earpieces are also better for the health of the inner ear than most other types. Sam Costello at About.com

“The noise around us can contribute to cause us to change how we listen to an iPod. If there’s a lot of noise nearby, it’s likely that we’ll turn up the iPod’s volume, thus increasing the chances of hearing loss. To cut down on, or eliminate, ambient noise, use noise-deadening or –cancelling headphones. They’re more expensive, but your ears will thank you”. 

Chris Woodford, post for ‘Explain That Stuff.com’, provides an in depth description of those core distinctions between earpieces and speakers. Despite fundamentally working in the same way, there are variations involving the two, it seems. He says,

“The biggest difference between loudspeakers and headphones is, of course, size. A loudspeaker needs to set all the air moving in a room so you can hear the sound it’s making, but the speaker in a headphone only has to move the volume of air inside your ear canal. That’s why it can be so much smaller and more discreet”.

 If, even in fact this tech discuss, you are still interested in considering what is going on to your headphones, the Youtube user Cayde Brown features a series of video lessons labeled ‘Take Apart’, which may be of significance. In one episode (which I’ll link HERE), Cayde takes a set of headsets apart and reveals to us precisely how they operate.