Best Noise Cancelling headphones

Today’s market is represented by thousands of models of headphones: from cheap Chinese NoName-plugs to exclusive. Prices driven by customer requests and technology. On the technology of best noise cancelling headphones, installed in most closed-type headphones, today we will talk, and most importantly – we will find out the reasons for the headache with long listening to such “ears”.

Active noise cancellation system. History and working principle

The history of development of active noise cancellation system (hereinafter – ASP ) begins in the distant 1934 , when inventor Paul Lug receives a patent describing the principle of suppression of sinusoidal signals emitted by the loudspeaker. In 1950, Lawrence Vogel first implemented a noise suppression system in helicopter cockpits and aircraft parlors.

Prior to the headphones, ASP reached back in 1957 , when Willard Meeker on the presented working model of overhead headphones was able to cut off noise at an audio range of 50 to 500 Hz. The first serial model of headphones with active noise reduction was introduced by Bose in the late 80’s and was used in aviation.

best noise cancelling headphones

Bose Quiet Comfort: The Beginning

The principle of the ASPnet, in terms of physics, is very simple. Any sound is represented by a wave, so you can create its mirror image – an inverted wave that completely extinguishes the original one.

Inside the headphones, equipped with an active noise reduction system, there are microphones. Their task is to measure the level of ambient noise. The external audio signal is converted into an inverted wave and transmitted to the main speaker. The new wave acts in antiphase (minus the useful signal – music) to noise and, thus, reduces its sound to zero.

Headache

It would seem that the use of technology of active noise suppression should significantly improve the life of avid music lovers who do not represent a way to work, walks or active rest without headphones bending headphones, musical drive and rhythm. The number of models equipped with ASP is really growing by leaps and bounds . The market includes headphones of various price categories and form factors: from inexpensive compact gags to weighty studio monitors. The noise cancellation system is being improved every day, the quality of music playback is growing, manufacturers are finding new and new marketing solutions for the popularization of headphones with Noise Cancelling. But there is a category of people who, with all their positive attitude towards portable sound, are forced to abandon all technological advantages of “perfect headphones” for one simple reason – intolerance of the system of active noise suppression .

Wearing headphones with an active noise reduction system and going to the street, you yourself without understanding, deceive the brain. Going to the meeting passers-by, a noisy track, the rumble of the wheels, a sharp wind – the organs of vision clearly draw a picture of what you are on the street. But the organs of hearing testify to complete silence. This discrepancy causes the brain to be confused. Alas, the headache is assured.

Reason two: monotonous stimulus.

There is only one “but”. As a result of such constant noise jamming, monotonic sound waves act on the eardrums. This does not mean that we should hear a rumble or any extraneous noise. The brain perceives only a variety of sonic tones for a particular audio or track, but the nervous system … The action of such vibrations is the principle that is the basis of the active noise cancellation system and it is impossible to predict which organism it will lead to nausea and headaches.

Reason three: silence is not always calm.

Despite the fact that listening to music in headphones with an best noise cancelling headphones system about absolute silence can not be said, the very principle of the ASPnet intersects with the very “absolutely quiet room”. People, whose body is not adapted to this type of headphones, will feel headache and nausea after 1.5 – 2 hours of operation.

The fourth reason: the enemy is my bass

Depending on the height, all sound frequencies with equalization are divided into: high, medium and low. The system of active noise suppression is best handled precisely with the cutoff of low frequencies, which are predominantly saturated with the surrounding noise of the street. Worse things are high, because there is a risk of setting a useful sound signal, represented by music.

Mirror sound wave, reproduced in antiphase with the purpose of suppressing ambient noise, is most saturated with low frequencies . Low frequencies cause maximum vibrations when exposed to liquid, and if you take into account the fact that the human vestibular apparatus is filled with endolymph , then the constant vibrations from the bass bass and cause a headache.

Reason five: structural disadvantage

Another reason why an owner of headphones with active noise reduction system can constantly accompany headaches is too tight a headband. However, this is a common problem with overhead headphones and it’s hardly worth blaming ASP.

How to avoid useless acquisition

Of course, best noise cancellation headphones have several advantages: listening comfort, high level of sound detail and safe volume level. Alas, to foresee how exactly your body will react to ASP. Before you give your blood.

 

Important Things to Remember About a robots.txt File

A robots.txt generator is a special kind of tool that will allow you to generate a robots.txt file. You know well that this file is a very useful text file for it protects your website pages from the behavior of web crawlers, particularly search engines. A web crawler like a search engine crawls or visits websites in order to gather information about the contents of a website. However, there may be some web pages that you do not want web crawlers to visit or index. And to inform them about which pages to visit or not, you will have to use the robots.txt file.

robots.txt generator

But using this file is not just as simple as it may be. When utilizing it, you should take note of several important things about it. These are discussed below.

  • A web crawler may find it difficult to find the robots.txt file upon arriving at a website. If it fails to find one, it will crawl all the pages in the website. So the remedy for this is to place the robots.txt file in the top-level directory of a website so that it can easily be found.
  • Take note that the robots.txt filename itself is case sensitive. So once you have created this text file, make sure that its name is exactly “robots.txt” and not “ROBOTS.txt” or “robot.TXT” or “ROBOTS.TXT”.
  • Take note that there are some web crawlers that will choose to ignore your robots.txt file. Such crawlers are those owned by malicious agents like hackers of information.
  • You can see the robots.txt file of any website. To do so, just attach a “/robots.txt” at the end of any URL or domain. And this implies that anyone can also see what pages you want web crawlers to crawl and those that you do not want to be crawled. For that reason, it is not recommended to use a robots.txt file to protect private or sensitive information.
  • All the subdomains of a root domain should have their own robots.txt file. So for example, if you own a blog, its root domain would myblog.com and a possible subdomain is blog.myblog.com. Both of these should have their own robots.txt file.
  • It is recommended to indicate the location of sitemaps at the bottom part of a robots.txt file.

Now, you know the important things to remember about a robots.txt file. With such knowledge, you can now use the file in a much better way knowing some of its limitations and also some of its advantages. Now, if you are interested in creating your own robots.txt file but you somehow find it difficult to do so, then what you need is the robots.txt generator which is a tool that will automatically produce a robots.txt file for you.