如果您插入了耳机，移动车辆的背景噪音（持续鸣喇叭）或飞机引擎的轰鸣声可能会打扰您。戴上像降噪耳机(Noise-canceling headphones)这样通用的东西可以让你免于不适。这是一篇描述什么是降噪耳机的帖子，哪些是最适合您和您的需求的 - 以及它们是如何工作的？
什么是降噪耳机
顾名思义，降噪耳机是一种音频技术，可以产生静音，而不是噪音。这些设备专门设计用于防止声波到达您的耳朵。因此，当插入降噪耳机时，降噪耳机会在噪音很大的区域营造出异常舒适和宁静的聆听环境。
降噪耳机的工作原理
降噪耳机具有内置音频处理器，可检测声音并产生相反的波形。通过耳机驱动器发送的这种相反的波形或反波消除了侵入的声波。与手机不同，降噪耳机不会发出辐射。因此，它们不会真正构成频繁使用手机可能产生的威胁，因此可以安全使用。
一般来说，有3种类型的降噪耳机可以互换使用，但表现出细微的差异。
- 采用被动降噪技术的耳机
- 具有主动降噪技术的耳机
- 具有自适应降噪技术的耳机
这里有一些重要的事情要记住，以便为您选择合适的。
采用被动降噪技术的耳机(Headphones with Passive Noise Cancellation technique)
这些耳机更多地依赖于一种被称为“噪音隔离”的现象。这是耳机中最常见的降噪技术。耳机的设计使其形状和使用的材料可以阻挡噪音进入您的耳朵。额外的填充物充当垫子，在您的耳朵周围形成牢固的密封。
采用被动降噪(Passive Noise Cancellation)技术的耳机在需要隔离不规则和高频声音的情况下效果最佳。尽管目的非常有效，但它们体积庞大。因此，如果您正在寻找更好更轻便的替代品，请尝试使用隔音耳塞。
采用主动降噪 (ANC) 技术的耳机(Headphones with Active Noise Cancelling (ANC) Technique)
像被动降噪(Passive Noise Cancellation)一样，ANC耳机也使用它们的形状和设计来静音外部噪音。除此之外，他们还使用先进的技术。例如，它有一个小型的内置音频处理器，它可以检测和分析传入噪声的声音模式，然后通过生成镜像“抗噪声”信号来消除噪声。所以，基本上这些耳机所做的就是发出一个与它所捕获的波直接相反的波。在此过程中产生的声波波峰和波谷相互交汇，相互抵消，形成一条平坦的线。
如果您经常旅行，那么带有ANC的耳机会成为帮助您体验安静的正确工具，即使在飞机发动机的轰鸣声或交通繁忙的情况下也是如此。此外，这些耳机可以帮助您在这些环境中集中注意力或入睡。
话虽如此，这些耳机存在一个不足之处——ANC耳机需要电池来激活其降噪功能。添加的组件导致价格和重量的增加。
具有自适应降噪技术的耳机(Headphones with Adaptive Noise Cancelling Technique)
自适应噪声消除(Noise Cancellation)是估计被加性噪声或干扰破坏的信号的替代技术。这种技术在耳机行业相对较新。它与前者的不同之处在于它根据周围噪音的水平和类型调整消除强度。因此，当背景噪音很大（火车隆隆声）时，噪音消除较高（更强），而当背景噪音较低（喋喋不休、婴儿哭声）时噪音消除较小。
如果您的耳机采用此技术，建议激活此模式。此外，某些应用程序甚至允许您微调设置并设置所需的降噪级别。自适应降噪(Noise Cancelling)技术有一个缺点 - 降噪量越高，它对声音的清除就越积极。这会对语音质量产生负面影响。
总而言之，这些降噪耳机的实用性在很大程度上取决于您打算用耳机做什么，以及打算在哪里使用它们。它们并不完美，因为它们不能创造安静或完全消除噪音，而只能减少它。亚马逊(Amazon)上有一些最好的。
How do Noise-cancelling headphones work?
If you have your earphoneѕ plugged-in, the background noise of moving vehicular traffic (continuous honking) or the roar of аn airplane engine can bother you. Wearing sоmething universal like Noise-canceling headphones can save you from the discomfort. Here’s a post describing what exactly is a noise-canceling headphone, which ones are the best for you and your needs – and how do they work?
What are Noise-canceling Headphones
As the name suggests, the noise-canceling headphone is a piece of audio technology that creates silence, rather than noise. These devices are designed specifically to prevent sound waves from reaching your ears. As such, when plugged in, noise-canceling headphones create an exceptionally comfortable and restful listening environment in areas with a loud noise.
How do noise-canceling headphones work
Noise canceling headphones have a built-in audio processor that detects sounds and produces the opposite wave pattern. This opposite wave pattern or inverse wave sent through the driver of your headphone cancels the intruding sound wave. Unlike mobile phones, noise canceling headphones don’t emit radiation. So, they don’t really pose a threat that may arise from frequent use of a mobile phone and thus, are safe for use.
Generally, there are 3 types of noise canceling headphones that are used interchangeably but show subtle differences.
- Headphones with passive noise cancellation technique
- Headphones with active noise cancellation technique
- Headphones with adaptive noise cancellation technique
Here are some essential things to remember to pick the right one for you.
Headphones with Passive Noise Cancellation technique
These headphones rely more on a phenomenon known as ‘Noise Isolating’. It is the most common type of noise canceling technique available in headphones. The headphones are designed in such a way that its shape and used materials block noise from reaching your ears. The extra padding acts as a cushion to form a strong seal around your ears.
Headphones with Passive Noise Cancellation technique work best in conditions requiring isolation of irregular and high-frequency sounds. Although very efficient in purpose, they are bulky. So, if you are looking for a better and light alternative, try noise isolating earbuds.
Headphones with Active Noise Cancelling (ANC) Technique
Like Passive Noise Cancellation, ANC headphones too, use their shape and design to mute external noise. In addition to this, they use advanced technology. For example, it has a small built-in audio processor, which detects and analyzes the sound pattern of incoming noise and then cancels noise by generating a mirror “anti-noise” signal. So, basically what these headphones do is emit a wave that is the direct inverse of what it’s capturing. The peaks and troughs of the sound waves generated in the process meet one another and cancel each other out, resulting in a flatline.
If you travel a lot then, headphones with ANC come across as the right tool to help you experience quietness even in the roar of an airplane engine or in heavy traffic. Furthermore, these headphones can help you concentrate or sleep in these environments.
Having said that, there’s one shortfall associated with these headphones – ANC headphones require a battery to activate their noise canceling feature. The added component results in an increase in both, the price and weight.
Headphones with Adaptive Noise Cancelling Technique
Adaptive Noise Cancellation is an alternative technique of estimating signals corrupted by additive noise or interference. This technique is relatively new in the headphones industry. It differs from the former in a way that it adjusts the strength of cancellation based on the level and type of the surrounding noise. So, the noise cancellation is high (stronger) when background noise is loud (train rumbling) and small when background noise is low (chatter, baby cries).
If your headphones feature this technology, it is advisable to activate this mode. Plus, some apps allow you to even can fine-tune the settings and set your desired level of noise canceling. Adaptive Noise Cancelling technique has one disadvantage – higher the amount of noise cancellation the more aggressively it cleans the sound. This negatively impacts the voice quality.
In all, the utility of these noise-canceling headphones largely depends on what you intend to do with your headphones, and where you intend to use them. They are not perfect as they cant create silence or completely eliminate noise, but merely reduce it. Some of the best ones are available here on Amazon.
