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Noise blocking headphones insulate your ear from outside sounds to reduce the amount of outside noise allowing you to better hear and focus on the sounds from the headphones.
Headphones in general are used to hear music when one is in an environment where it is not convenient to play the music out-loud. Isolation headphones are similar except that it is used when the user wishes to have an even better hearing experience as the headphones will cancel out the noise from the outside environment.
Both are cool in some or the other way. They both have their advantages and disadvantages. Headphones are of various type: over-ear, on-ear, noise cancelling, gaming, etc. They are usually bigger in size when compared with earphones but offer a better noise isolation. They can be wired or wireless. Whereas, earplugs are small in size and fits directly in your ear canals offering a great sound quality and perfect noise isolation from the world. They can be in neckband style, wired or truly wireless.
QC3 (QuietComfort) headphones are made by a company called Bose. These noise-cancelling headphones reduce the amount of noise around the listener for a more comfortable listening session. The QC3 headphones feature a compact design that is worn on the ear with cushy ear pads.
The headphones that are rated the highest for noise cancellation are Bose headphones. They are recommended for long flights and for times when you will want to cancel out outside noise.
Any unwanted noise is muted with the noise cancelling headphones. For example if there is a baby on the plane that is crying. The headphones will mix the noise from your music/media and the external noise and cancels out the external noises.
According to an article on technology website CNET, where several noise-cancelling headphones were compared, the headphones with the best rating were the PSB Speakers M4U 2 Active Noise Cancelling Headphones.
Usually, you can't add active noise cancelling to existing headphones. Noise-cencelling headphones have a built-in microphone that listens to the sound around the headphones so that the electronics can cancel the noise.
There are many places where one can get Sennheiser noise canceling headphones. One can get Sennheiser noise canceling headphones at popular on the web sources such as Best Buy and Target.
http://reviews.cnet.com/best-noise-cancelling-headphones/ This site includes different brands of noise cancelling headphones. Local electronics stores may hold them in stock.
Noise reduction headphones are rated based on decibel readings. The decibel scale is logarithmic. A change of 10 dB means a tenfold change in loudness. Noise reducing headphones can block out 40 dB of ambient noise.
According to an article on technology website CNET, where several noise-cancelling headphones were compared, the headphones with the best rating were the PSB Speakers M4U 2 Active Noise Cancelling Headphones.