Be it a pair of classic wired earphones, fitness-oriented neckbands, the convenient true wireless earbuds or a pair of over-the-ear headphones, there are a couple of terms you come across every time you want to purchase a new pair. One of them is noise cancellation, while another is noise isolation.
Today, we look at what exactly these terms mean, what makes them different from each other, and also look at which of the two features you should look for in your next pair of earphones, earbuds or headphones.
Noise isolation is, as the name suggests, isolating noise in/away from an area so it doesn’t leak, or reach out of the set confines. Something as simple as covering your ears with your hands or putting in some earplugs in an airplane to cut off the noise when taking off could be the simplest forms of noise isolation.
In the context of audio accessories like earphones and headphones, noise isolation refers to the addition of specific material where the earphone tips or headphone muffs come in contact with your ears. This is usually some sort of foam padding, and its purpose is to block the unwanted sound from outside, so you can hear your music with minimal disturbance from the traffic outside when in a jam.
Noise isolation can be found on any earphones or headphones which come with a sound-blocking mechanism like silicone tips, memory foam, etc. As an added benefit, noise isolation also prevents sound from your earphones or headphones from escaping outside, preventing people seated close to you on a subway from listening to whatever you’re grooving to.
However, poor noise isolation implementations could mean your music is audible outside and unwanted noises from outside manage to find their way in. This is what we call “leaking”. Leaking is present at some level on all earphones/headphones. But with better quality earphones or headphones, sound leakage is on the lower side.
As effective as noise isolation is on a pair of headphones or earphones, there are still situations where sound, or rather, certain frequencies of sound will still get through even the best headphones. This is where a newer, more advanced technology called noise cancellation comes in.
Unlike noise isolation, which is a physical implementation, noise cancellation is an electronic one. It involves sensing audio from outside the earphones/headphones, and emitting anti-noise signals that counter and “cancel out” the unwanted sound, hence giving the tech its name.
Noise cancellation is battery-powered and will drain the battery of your audio accessory faster when switched on. This is the reason most noise cancellation-enabled devices will come with some form of a toggle.
When earphones/headphones use the emission of sound signals to actively cancel out unwanted frequencies, the technology in use is referred to as Active Noise Cancellation, or ANC. This is exactly what we explained in our Noise Cancellation section above.
Passive Noise Cancellation is the use of physical passive barriers to block out sound, with no electronic mechanism to accomplish this. Simply put, it is no different than noise isolation, with the term passive noise cancellation just used often in the context of audio equipment, while noise isolation is a broader, more general term.
Passive noise cancellation is also considered to be more of a marketing term, similar to ENC or environmental noise cancellation. Note that unless a pair of headphones or earphones deliberately mention active noise cancellation (ANC), they’re unlikely to feature an electronic signal-emitting mechanism to block unwanted noise.
There are advantages and disadvantages to both methods of getting rid of unwanted sound.
Noise isolation, being non-electronic in nature, has zero effect on the battery life of wireless earphones. Noise isolating headphones are also usually cheaper and simpler to use than their noise cancelling counterparts.
While noise isolating headphones may not be the most effective at cutting off constant humming or low frequency sounds like moderate traffic or your ceiling fan at full speed, there may be certain situations like loud industrial areas, where a pair of good noise isolating headphones could theoretically outperform noise cancelling headphones.
Coming to noise cancelling headphones, the advantages are clearer sound as a result of better cancelling of unwanted frequencies, but disadvantages include higher price and usually lesser battery life when ANC is in use.
This is why good quality headphones like the JBL Quantum 800 and many others will implement both noise isolation as well as noise cancellation to offer the best experience. However, these headphones will also cost more.
If your budget allows, a good pair of noise cancelling earphones or headphones would, in my opinion, be a better investment long term. This is because even when you want to save on battery life, you can simply turn off the ANC toggle on most audio accessories.
If this is not the case, you can still opt for cheaper noise isolating earphones or headphones, which have also improved vastly over the years, while still being affordable and battery-friendly.
However, when it comes to cheaper earbuds, earphones or headphones that claim to offer “noise cancellation,” either stay clear or look up trustworthy reviews first. There may be fine print that mentions passive noise cancellation, which as we explained above, is not really true noise cancellation.
The budget hearable may also actually feature true active noise cancellation that is simply not as good. This would usually mean unwanted hissing sounds when ANC is turned on, or a simple lack of effectiveness. Needless to say, this is something you don’t want.