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