| Sometimes we get so tired with our hectic and | | | | noise before reaching your ears. Then the |
| noisy world. We simply wish we could go to a | | | | noise-cancellation circuitry which is housed |
| tranquil forest and rest our minds for a few | | | | in an external module, essentially inverts |
| hours; to look for peace and calmness. Or | | | | the captured signal which turns the noise's |
| sometimes when you are in crowded place or in | | | | sound wave upside down. So in just a short |
| place where the background noise is a bit too | | | | period, the noise-cancellation system adds |
| loud, it gets simply impossible to have a | | | | the sonic opposite of the external noise to |
| conversation with the person sitting next to | | | | whatever you're listening to and thus |
| you. It is irritating as you would have to | | | | eliminating most of the pollution and leaving |
| strain to hear what he is saying, and in turn | | | | you with just your music. |
| you have to shout so he can hear what you are | | | | |
| saying. Now, thanks to technology, the latest | | | | There are a few disadvantages of |
| innovation you can actually achieve this-The | | | | noise-canceling headphones such as: |
| Noise Canceling Headphones. | | | | |
| | | | - These headphones consume power and hence |
| Theory: | | | | batteries are to be used which must be |
| | | | occasionally replaced. |
| Noise-canceling headphones reduce unwanted | | | | |
| ambient sounds by means of active noise | | | | - Some headphones may not cancel all sound |
| control. The theory behind this is that by | | | | effectively as they can be overloaded by |
| picking up ambient sound with the microphone | | | | low-frequency pressure waves, distorting the |
| and reproducing it out of phase, you can | | | | desired signal. |
| actively cancel or "null" out background | | | | |
| noise. Essentially, this involves using a | | | | - They may introduce additional noise, |
| microphone, placed near the ear, and | | | | usually in the form of high-frequency hiss. |
| electronic circuitry which generates an | | | | |
| "antinoise" sound wave 180° out of phase | | | | - Size is an issue here as they are generally |
| from the sound wave arriving at the | | | | more bulky than traditional headphones. |
| microphone. This results in destructive | | | | |
| interference, which cancels out the noise | | | | Your solution against noise: |
| within the enclosed volume of the headphone. | | | | |
| | | | The noise cancellation headphones are a boon |
| Passive vs. Active noise cancellation : | | | | for frequent fliers. You can now escape the |
| | | | continual background noise of the engines and |
| The passive or the low-tech, way to cancel | | | | the plane. You would be able to enjoy your |
| noise is simply to wear closed-back, | | | | plane ride peacfully. When you use them, you |
| circumaural -around the ear headphones or | | | | can enjoy movie soundtracks or music because |
| very snug ear buds. These shield your ears by | | | | there is less background noise to fight |
| sealing them off from the outside world. | | | | against. And, if you're looking for a |
| Active noise cancellation, on the other hand, | | | | relaxing peaceful moment, you know what to |
| is far more complicated. First the | | | | do-just hook on to your noise cancellation |
| microphones on each earpiece, detect ambient | | | | headphones. |