{"id":5688,"date":"2020-07-23T19:42:56","date_gmt":"2020-07-23T19:42:56","guid":{"rendered":"http:\/\/auribluz.com\/?p=5688"},"modified":"2022-11-26T10:11:19","modified_gmt":"2022-11-26T08:11:19","slug":"cancelacion-de-ruido","status":"publish","type":"post","link":"https:\/\/auribluz.com\/en\/noise-cancellation\/","title":{"rendered":"Active and passive noise cancellation: what it is, how it works, advantages and disadvantages of using it"},"content":{"rendered":"

He ambient noise<\/strong> is a very important factor that determines the final sound quality of headphones, especially if we do not have an acoustically isolated room and we use our headphones in public places. This is when the technology of Active and passive noise cancellation<\/strong> play an important role.<\/p>\n\n\n\n

Below we will see what types of noise cancellation there are, how it works, advantages and disadvantages.<\/p>\n\n\n\n

Related<\/strong>: best noise cancelling headphones<\/a><\/strong><\/p>\n\n\n\n

Types of noise cancellation<\/h2>\n\n\n\n
  • Active noise cancellation<\/strong>, which we will also call active technology.<\/li>
  • Passive noise cancellation<\/strong>, also known as sound insulation.<\/li><\/ul>\n\n\n\n

    What is active noise cancellation and how does it work?<\/h2>\n\n\n\n

    The active noise cancellation systems<\/strong> either ANC<\/strong> (Active Noise Control) is an active technology capable of eliminating outside noise. It is achieved by eliminating that "outside noise" thanks to the theory of wave interference. Easily explained, it would be as follows:<\/p>\n\n\n\n

    Sound is a low frequency wave<\/strong> which complies with the principle of superposition, that is, when two or more waves meet at the same point, the resulting wave is the vector sum of the waves that have met at the same point. Thanks to this characteristic, an artificial sound wave is created that if we add it to the original wave results in the total or partial cancellation of a part of it<\/strong>. This is what is known as destructive interference of waves<\/strong>.<\/p>\n\n\n\n

    In the headphones, we will hear the sum of the original signal (the music) with the ambient noise<\/strong>If the headphones have active noise cancellation, there will be an artificial signal that will cancel out that ambient noise. This artificial signal is nothing more than a sound wave created by an electronic circuit.<\/p>\n\n\n\n

    \"noise
    Step by step noise cancellation explanation<\/figcaption><\/figure><\/div>\n\n\n\n

    How can an artificial signal cancel out only ambient noise?<\/h3>\n\n\n\n

    It does so through one or more Microphones located in the body of the headset or in the cable that pick up ambient sound<\/strong>, then they process it and generate an identical signal, but of the opposite phase and when this new signal is reproduced together with the original signal, the result is a destructive interference<\/strong> and a sound free of ambient noise.<\/p>\n\n\n\n

    It is also capable of eliminating sound leaks caused by hair, glasses, ear shape and head movements<\/strong>.<\/p>\n\n\n\n

    However, This theory is not entirely perfect<\/strong>Its operation is limited by the main frequencies that make up the noise signal, that is, that with low frequency noise<\/strong> and the constant type produced by a motor works very well. However, the problem is with high frequency sounds, but this can be solved with passive techniques, i.e. acoustic insulation systems, which we will talk about later. But generally, they give good results.<\/p>\n\n\n\n

    What many people don't know is that the Active noise cancellation is a feature that can be turned on and off depending on the user's needs.<\/strong>If we deactivate them, we reduce the consumption of the headphones, without losing sound quality.<\/p>\n\n\n\n

    Disadvantages of active noise cancellation<\/h3>\n\n\n\n
    • They are systems that need external energy<\/strong>, that is, the headphones have to be charged with a USB connector, with small batteries or with rechargeable batteries.<\/li>
    • It is possible that the same system can slightly modify the final signal<\/strong>This may degrade the signal or introduce annoying background hiss.<\/li>
    • Incorporating this system into a headset makes your selling price increase<\/strong>.<\/li>
    • It is possible, although less and less, that increase in size and weight<\/strong> of the headphones that have this system.<\/li><\/ul>\n\n\n\n

      What is passive noise cancellation and how does it work?<\/h2>\n\n\n\n

      He passive noise cancellation system<\/strong>, also called sound insulation<\/strong>, is responsible for preventing outside sound from entering our auditory system. This effect is achieved by placing insulating material<\/strong> between the casing of our earphone and the part that will be attached to our ear.<\/p>\n\n\n\n

      This technology is the simpler and cheaper<\/strong>, which is why it is used in all headphones today. However, it is not enough because it only attenuates outside noise, but does not cancel it<\/strong>.<\/p>\n\n\n\n

      This feature, even if we don't think about it, It can also become an advantage<\/strong> because we can hear ambient noises that may be necessary for our safety (such as the engine of a car or bus). In addition, they do not need to be charged in any way.<\/p>\n\n\n\n

      The best headphones with that type of system are the on-ear and over-ear<\/strong>, also known as supraaural and circumaural<\/strong> respectively. In-ear headphones (those that are NOT headband-style), on the other hand, usually have little passive noise cancellation, especially if they do not fit well in the ear.<\/p>\n\n\n\n

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