Headphones are an incredibly common sight in this day and age. Its a useful invention, not only making music incredibly portable, with out annoying those around you. But few people know just how they work. Headphones are essentially two small speakers, and function in the same way.
A speaker is made out of a few simple parts. The most important of which being the electromagnet and the cone. An electromagnet is a conductor with a wire coiled around it. Current is then passed through the coil, and a magnetic field is created. The North and South poles of the field are determined by the direction of the current, so by reversing the current, you also reverse the poles, which are on the front and back of the magnet (depending on the direction). The cone is just a paper cone attached to the magnet, which is able to move with the magnet its self.
As the electromagnet's poles are switched it is is also attracted and repelled to a stationary magnet in the speaker. The stationary magnet's poles don't change. Electrical signals are sent through the wire, switching the currents in a specific pattern. As the magnet moves back and forth, being attracted and repelled, it also causes the cone to move back and forth with it. The moving of the cone vibrates the air waves with it, and the human ear detects these vibrations in the air, and turn them into what we know as sound. This is an exaggerated version of how a speaker vibrates
headphones are built as small enough speakers to fit around our ears for a more "private" sound. there are basically two kinds of headphones today: Circumaural headphones, and in-ear headphones.Circumaural headphones have large pads around the actual speaker to fit around the ear itself, sealing the ear from most outside noise, giving the sound produced a better quality. some also fit on the ear, but the speaker still lies on the outside of the ear.
In-ear headphones are more commonly known as "earbuds". earbuds have even smaller speakers than the Curcumaural, but instead of the speaker being positioned directly next to the ear, the speakers are placed inside the outer ear, and some even go into the ear canal.earbuds do not reduce outside noise as much as their counterpart, but are much smaller and more compact.
Headphones are an incredibly common sight in this day and age. Its a useful invention, not only making music incredibly portable, with out annoying those around you. But few people know just how they work. Headphones are essentially two small speakers, and function in the same way.
A speaker is made out of a few simple parts. The most important of which being the electromagnet and the cone. An electromagnet is a conductor with a wire coiled around it. Current is then passed through the coil, and a magnetic field is created. The North and South poles of the field are determined by the direction of the current, so by reversing the current, you also reverse the poles, which are on the front and back of the magnet (depending on the direction). The cone is just a paper cone attached to the magnet, which is able to move with the magnet its self.
As the electromagnet's poles are switched it is is also attracted and repelled to a stationary magnet in the speaker. The stationary magnet's poles don't change. Electrical signals are sent through the wire, switching the currents in a specific pattern. As the magnet moves back and forth, being attracted and repelled, it also causes the cone to move back and forth with it. The moving of the cone vibrates the air waves with it, and the human ear detects these vibrations in the air, and turn them into what we know as sound.
This is an exaggerated version of how a speaker vibrates
headphones are built as small enough speakers to fit around our ears for a more "private" sound. there are basically two kinds of headphones today: Circumaural headphones, and in-ear headphones.Circumaural headphones have large pads around the actual speaker to fit around the ear itself, sealing the ear from most outside noise, giving the sound produced a better quality. some also fit on the ear, but the speaker still lies on the outside of the ear.
In-ear headphones are more commonly known as "earbuds". earbuds have even smaller speakers than the Curcumaural, but instead of the speaker being positioned directly next to the ear, the speakers are placed inside the outer ear, and some even go into the ear canal.earbuds do not reduce outside noise as much as their counterpart, but are much smaller and more compact.
sources-
http://www.google.com/imgres?um=1&hl=en&sa=N&biw=1366&bih=667&tbm=isch&tbnid=DqreKRGOEX7RcM:&imgrefurl=http://scienceblogs.com/aardvarchaeology/2011/11/in_my_earbuds_lately_3.php&docid=P9ioz4FbatR9mM&imgurl=http://scienceblogs.com/aardvarchaeology/upload/2010/05/in_my_earbuds_lately/creative-earbuds.jpg&w=450&h=386&ei=EgpgT_OpE4Pt0gH5iI3OBw&zoom=1&iact=rc&dur=375&sig=110918448244524790364&page=1&tbnh=136&tbnw=169&start=0&ndsp=21&ved=1t:429,r:0,s:0&tx=74&ty=22
http://www.google.com/imgres?um=1&hl=en&sa=N&biw=1366&bih=611&tbm=isch&tbnid=D4Wi_owpN_wXrM:&imgrefurl=http://www.wired.com/gadgetlab/2008/10/review-sony-noi/&docid=vaXunj8Pf1wSaM&imgurl=http://www.wired.com/images_blogs/photos/uncategorized/2008/10/02/sony__mdrnc500d_head.jpg&w=450&h=650&ei=nApgT6X2Osjx0gGu1-TJBw&zoom=1&iact=hc&vpx=915&vpy=286&dur=146&hovh=270&hovw=187&tx=92&ty=293&sig=110918448244524790364&page=2&tbnh=133&tbnw=94&start=26&ndsp=32&ved=1t:429,r:5,s:26