What is Passive & Active Noise

Noise Cancellation-Active & Passive

Many types of ambient sounds can interfere with or even block the sounds coming through their headphones. If you try a headphone on the plane, then you know the problem well: The roar of the engines makes it difficult to hear the music through the speakers. Fortunately, noise-cancelling headphones can provide a more enjoyable listening experience.
Noise cancellation in headphones is a system by which unwanted sound from outside does not interfere with the music being piped in by source. There is two type of noise cancellation in headphones. Passive and active noise cancellation. There is two jargon used in the headphones industry. Noise isolation headphones and noise cancelling headphones. One should understand the difference. This is what we are putting up here without involving much of technical words.

What is PASSIVE NOISE cancellation

Passive noise cancellation is also called” Noise isolation”. In such case, physically noise is stopped to come in the ear canal by using heavy sound absorbing the material. That means they are packed with layers of high-density foam or other sound-absorbing material, which makes them heavier than normal headphones. The idea here is a physical barrier between your ear and the offending sounds. It all depends on how good is a seal to stop the unwanted sound coming from the neighbourhood. Noise isolating headphones, at best, can muffle everything around you quite well. The only problem is, In-ear models, the earbuds are heavy and oversized. Such headphones with noise isolation don’t need batteries. In-Ear-Headphones and Over-the-Ear- Headphones are best in noise isolation.

What is ACTIVE NOISE cancellation

Active noise cancellation is normally called “Noise Cancelling ”  headphones. Such headphones cancel most of the noise by noise isolation and also by noise cancellation. In noise cancellation, some fancy processing creates inverse waves which get fed back into the headphones. These inverse waves cancel out the ambient sound. This process is called active noise cancellation or in simple words noise cancellation. Noise cancelling works best with low droning sounds, like car engines, aeroplane engines, air conditioners, etc. But could never reduce baby cries.

What is IP78

IP refers to the International Protection Rating (Ingress Protection Rating). They are used to define levels of sealing effectiveness of electrical enclosures against intrusion from foreign bodies (tools, dirt, etc) and moisture.
IP78 indicate
First Digit 7 indicate Solid Protection
Second Digit 8 indicate Liquids Protection
IPX5 –X-No protection from dust.5- Protects from water jets in any direction

Technically Management of Noise Cancellatio/Isolation and Ingress Protection Rating

NOISE CANCELLATION

Noise cancelling headphones use microphones to listen to the incoming sound, then some fancy processing creates inverse waves which get fed back into the headphones. These inverse waves cancel out the ambient sound
Noise cancelling works best with low droning sounds, like car engines, airplane engines, air conditioners, etc. Midrange sounds, like voices, are largely unaffected (though they may sound odd as the low frequency parts of the voices are cancelled out). Perhaps most sadly, that bane of any long flight, baby cries, aren’t reduced by noise cancelling.

NOISE ISOLATION

Noise isolating  headphones physically block ambient noise with their seal against your earMany in-ear and on-ear headphones isolate you from ambient noise. Some are better than others. The idea here is a physical barrier between your ear and the offending sounds.With in-ear headphones, how much sound they reduce is based entirely on how good a seal you’re able to get

International Protection Rating (Ingress Protection Rating)***

They are used to define levels of sealing effectiveness of electrical enclosures against intrusion from foreign bodies (tools, dirt, etc) and moisture.
IP78 indicate
First Digit 7 indicate Solid Protection
Second Digit 8 indicate Liquids Protection
IPX5 –X-No protection from dust.5- Protects from water jets at any direction