This podcast is about the human ear, it contains information on how the ear works, hearing loss, preventing hearing loss and more damage that can effect the ear and its consequences on your hearing Outer ear https://www.asha.org/public/hearing The outside of the ear is made up of the ear canal and the pinna. The ear canal is the part of the ear that is the hole you can see going into your head. The pinna is the soft tissue on the side of our heads that are visible, they are made from cartilage so that it can keep its strange shape, but this strange shape has a purpose. The shape of the pinna directs all sound waves that hit and direct it into the ear canal, which is the hole we talked about earlier Mid ear The middle ear starts with the eardrum that is at the end of the ear canal and then ends at the ossicles. The ossicles are 3 tiny bones that help to bridge the gap between the eardrum and the inner ear. When sound waves hit the eardrum they cause it to vibrate, which is transferred into the ossicles, which cause them to transfer the vibration into the inner ear. This process turns vibration from the air into vibrations in the inner ear which can be read Inner ear Inside the inner ear, there are multiple organs which do different jobs. The 3 arches that are above the snail shape are part of your balance system, without these, you would not know which way is up. The snail shell shape underneath this organ is called the cochlea. The middle ear puts vibrations into this organ, the vibrations travel inside the shell wich is filled with liquid and lots of nerve cells like hair. These nerves translate the vibrations into signals, which when sent to the brain cause you to perceive sound. Hearing loss https://www.hear-it.org/hearing-loss When your hearing gets worse it is known as hearing loss, this causes you to struggle to hear frequency’s and sounds, most commonly speech since it’s the frequency we hear the most. There are things you can do to prevent hearing loss however it will happen naturally over time because of age-related issues. The age-related hearing loss is also known as Presbycusis. Most peoples ability to hear will worsen in our 30s and 40s and gradually deuterate however the more common cause of loss of hearing is peoples constant exposure noise that they hear every day. Ways to Protect yourself from hearing loss Use earplugs Turn down the music Wear protective headphones Wear ear protection when you’re listening to live music Don’t put up with work noise Have a hearing detox If music at a party or sound anywhere is painful to listen to move away from the sound or turn down the music as soon as you can. If you don’t know if the sound could be damaging try follow this rule if you can’t talk to someone two meters away without shouting, the noise level could be damaging your hearing. Effects of hearing loss Can cause a reduced ability to understand other people, particularly in noisy situations. This can impact how you interact with family and friends, making it difficult to learn at school Tinnitus (constant ringing) http://www.betterhearing.org/hearingpedia/hearing-loss-prevention/tinnitus Tinnitus is when you hear a sound when then there isn’t any.People with this have said they hear a ringing, buzzing or clicking sound, Hearing tests see your doctor to check how healthy your hearing is as it’s a good idea to stop a hearing problem before it gets worse. Most hearing checks are free, painless and take just five to 15 minutes. You can do some of them for yourself in your own home, for example there are many downloadable programs online that test your own hearing on the computer. Hearing uses in jobs Owning well working ears is needed in sound engineering because its important that you can hear high level and low level frequency’s while analyzing sound. good hearing is needed for distinguishing sound quality. Reasons why having good hearing is important Hearing incoming traffic Music for entrainment Communication And Receiving a treatment If you do have hearing damage there are ways you can treat it, a common treatment is wearing hea ring aids. But permanent damage cannot be reversed! So please protect and look after your hearing This part of the podcast is about the perception of sound. The perception of sound is when we are able to tell where sound is coming from by using our ears, It is also known as sound localization. First I will talk about how we locate sound vertically The ears aren’t very good at locating vertical sounds. The brain locates the sound by pairing different frequency’s with locations, for example sounds or noises around 1000 and 10000 hz are heard from behind you while sounds or noises near 500 and 8000 hz are heard directly above your head. Because ears aren’t very good at locating vertical sounds you can trick the ear to think sounds are coming from a different direction than they actually are by using filtered noise. Now I will talk about how we locate sound binaurally Having two working ears allows us to locate the direction of binaural sound, this is because the brain uses both ears as two points of information. The brain uses this information and the time it takes for sound to get to each ear to locate where the sound is coming from. The brain also uses how load the sound is to locate the source but because really low frequency’s have longer sound waves this means that the ear will rely on the time for it to reach both ears instead of the level of sound or noise. The Haas effect is when all sounds arriving at the ear within the first 35milliseconds sounds like it is coming from the same direction. This is because the time witch the brain takes for the information to get from the ears to the brain is around 35 milliseconds. The Doppler effect is when the sound from a moving object appears to change frequency’s as it approaches and passes by you. This is commonly heard in ambulances and police cars, This is because when the object travels towards you its travels with small wavelength high frequency’s while when its traveling away you hear low wavelength and low frequency’s. The Franssen effect is when two speakers are placed to the left and right of the listener in a live room. The speakers are about 3 feet from the listener and at a 45 degree angle. Noise is played through the left speaker, it is faded out of the left and into the right speaker but there is no change in sound level during this. Most listeners will not notice the sound has moved and will still think it is coming out of the left speaker. This part of the podcast is how we measure loudness and the decibel scale ratios. Loudness Is measured in pressure levels (SPL) Ten times the pressure causes you to hear the sound at twice the volume. therefor if you moved the pressure up from 10spl up to 100spl the volume would double. The ratio for this example is 10 to 1 Decibel scale Decibels are the scales of ratios used to measure power, sound pressure this if for acoustic or watts for electric. Measuring this unit is called a bel but this is to big for most sounds so its divided by 10 giving us a decibel. Decibels go up in a logarithmic scale this means every 10db the sound seems twice as load 100 can be written as 10^2 = 100 (10 to the power of 2 = 100) You can use this to simplify the massive numbers when analyzing decibels which makes the easier to read. Fletcher-Munson equal loudness Pressure is measured in pascals. The smallest amount of pressure needed for us to hear is 0.000002rPa. While the loudest sound sounds which comes from rockets is around 100,000Pa We use the hearing of humans as a reference for measuring spl in decibels http://slideplayer.com/slide/6064998/18/images/3/Noise+Logarithmic+scale+used+:+decibel+(dB)+Sound+Pressure+Level+(SPL).jpg Loudness and frequency as the volume changes, you can hear different frequency’s in music, for example when you are listening to a song at a low volume you won’t be able to hear low frequency’s while you will be able to hear high frequency’s. While at a high volume you can easily hear the low frequency’s really easily https://archive.cnx.org/contents/[email protected]/hearing On a lot of older devices, you can normally find a loudness button, this will equalize your music so that you can hear all frequency’s instead of some dropping out at quiet volumes. On newer devices, it does this automatically.