Bone Conduction Technology, What is it, and How does it Work?
Bone conduction is the transmission of sound waves to the inner ear through the bones in a person’s head. Sound is traditionally heard when sound waves sent through the air are received by the ear, these waves travel down the ear canal and activate the ear drum. On the other side of the ear drum are three small bones called the ossicles, these pass the vibrations sent by the ear drum on to the part of the inner ear referred to as the cochlea, which in turn passes these signals along to the brain via the auditory nerve.
When using bone conduction technology, the vibrations from the sound waves are sent through the bones in the head directly to the inner ear and cochlea. Because the middle ear and ear drum are bypassed, many people who have hearing disabilities are able to hear sounds that are transmitted through bone conduction. Also, because the ear drum is not being activated a person listening to sound through bone conduction technology can still here surrounding noise as well. So, a runner listening to music with bone conduction headphones would still be able to hear an approaching vehicle or someone calling out to them.
A Safer Way to Listen to Music
Listening to music through bone conduction headphones can provide the user with better saftey. As discussed earlier because the main part of the ear is not used, surrounding sounds can still be heard, making this much safer for someone out an about. This also means that there is nothing inserted into the ear as in the case of ear buds, so there is no risk of damage, or discomfort this way. In addition to this, although listening to music at high volumes can still damage the cochlea causing hearing loss, this is less sensitive than the ear drum, and can be much safer if kept to a reasonable volume.
Why Your Voice Sounds Strange
An interesting fact about bone conduction, is that it is the reason people often find that their own voice sounds strange, or unpleasant when they hear a recording of it. This is because lower frequencies are transmitted more effectively so when we speak we hear our voices as being lower and deeper.
An Old Technology that is Continuing to Evolve
Bone conduction technology has been around for quite awhile. In fact, after his hearing began to deteriorate this was the method which Beethoven used in order to continue composing his great works. He attached a rod to his piano which he then held between his teeth so that the sound wave could be conducted through his jaw bone and he would be able to hear the music.Since then the technology has come a long way, now being able to produce high quality sound. By amplifying certain frequencies that are not as easily conducted through bone, a clearer and more familiar sound is created.
There are now bone conduction hearing aids that can receive sound waves conducted through the air, and convert them to vibrations to be send via conduction. The technology is being used to improve communications for workers underwater, or in conditions where ambient noise is too high, such as in the cockpit of a fighter jet. And bone conduction is even being used in more novel endeavors such as a pillow that transmits sound, or bus windows that play advertisements when they are leaned on.