Noise cancelling is also known as active noise cancellation,which is a powered system that requires a microphone and a battery to function.The microphone picks up the surrounding noise and sends the opposite frequency to the headphones to negate the unwanted noise.
Audio Technica ATH-ANC23 Inner
When active noise cancelling is on, it feels like you’re in a quieter place, but it does not cancel out all noises. The sound of human voices, loud music and every other, non-constant frequencies would not be cancelled out and you’ll still hear them. Usually the combination of active noise cancellation and passive noise isolation offers the best results.
Passive noise isolation is a more basic concept, however, very effective. It uses no batteries or microphone, just simple noise blocking by isolation. For over-ear headphones, the use of tight fitting ear pads play a crucial role in blocking out all external noises. For in-ear monitors, using double or triple flanged ear tips usually gives the best results.
Good noise isolating headphones will block up to 37 db of noise which means – complete isolation from normal conversation volume, especially once you play some music. Passive noise isolation blocks all outside sounds, from neighbors to loud music. This makes them very useful when you just want to have some peace and be quiet without being bothered by the outside world.
On the other hand, complete sound isolation can be dangerous in public places, like on the street when it’s good to know what is going on around you. Once you press the button to active noise cancelling, part of the background sounds will just disappear, making the illusion of a quieter environment.
Should I Choose Noise Cancelling or Noise Isolation?
Ultimately, it depends on your purpose and needs. You need to ask yourselves some questions: Do you want to enjoy music in an entirely quiet place? When and where will I use the headphones or earphones? I would say for me,noise cancelling headphones work best for traveling since I would like to have some quiet time on flight, however, there is a risk to balance, which is at the same time any important information regarding flights I could be missed out.