With more and more noise-cancellation headphones coming to the market, people are always getting confused about how to judge the quality and features on them. our technology director, Leo, who is very familiar with noise-cancellation technology and acoustics, he wants to give some tips you can use when looking at these headphones.
How many decibels can it lower/cancel out?
most people are only interested in this, but this alone is really not enough information for finding a good pair of active noise-cancellation headphones. I can say this standard is the one that matters the least, and a lot of the numbers thrown out in promotions are meaningless.
Why is that? Here is an explanation:
The number we are given in relation to decibel reduction (10dbs, 20dbs for example) comes from acoustical laboratories that run tests using pink noise. Pink noise is a relatively stable noise, and it’s a signal or process in which spectral density is inversely proportional to signal frequency.
To put it simply, the pink noise is stable and consistent. However, in real-world noise is unstable, and it contains more than a signal noise, for example, engine noise, voices, construction noise, and countless other sounds. The noise we hear in day to day living is much more complex than the pink noise used in acoustic laboratories. Therefore, the noise-cancellation effect of up to 20 decibels or 25 decibels will be specific to the lab test, but not noise out in the real world. Because of this, there are other factors to consider when looking at noise-canceling units. Basically, any noise-cancellation headphones that reduce decibels by at least 20db will be a good start.
Noise Cancellation Frequency Range
The Noise cancellation frequency range is the most important factor in evaluating a noise-cancellation headphone unit. As I mentioned before, in the real world, the situation is much more complex than in the laboratory, and the noise comes from many different sources in different frequency ranges. People can hear voices from the 20 Hz– 20K Hz range, so it simply doesn’t make any sense if the headphone can cancel 28 decibels, but it only works in the range of 100Hz to 400Hz. What good is canceling out decibels in a frequency you aren’t hearing, to begin with?
Therefore, the wider the noise-cancellation frequency range, the better the noise-cancellation headphone. If the manufacturer provides its spectrum, you can see how the noise-cancellation function works on different frequencies. In terms of the noise-cancellation technology today, it is optimal if the noise cancellation function works between a range of 80Hz to 1K Hz, or even wider.
The effects of Noise-Cancellation Technology on Acoustic/Audio Performance
We are talking about noise-cancellation audio headphones (in-ear/on-ear/over-ear), not sound-blocking earplugs, right? So, in terms of an audio headphone, we don’t want the noise-cancellation function to affect the integrity or quality of the audio very much. Therefore, it is very important that the headphone designer has great control over the headphone acoustics. The noise-cancellation function will affect the acoustic performance of a headphone to some degree, but if the headphone
There are many different parameters to evaluate good audio performance on headphones. To simplify things, I will list just three of them today, which are also the basic parameters we use to evaluate the acoustics performance: impedance, sensitivity, and frequency range. The easiest way to evaluate this is the higher the impendence and sensitivity, the better. Also, the wider the frequency range, the better. Keep in mind though, as I said before, there are many different parameters to judge the acoustics. The three parameters I listed are only a reference, but is good to use them in most cases.
How Comfortable are the Headphones When You Wear them?
Comfort is also a very important factor for noise-canceling headphones. In fact, it is a big factor with all headphones. Comfortability really depends on the industrial design and structure of the headphone. When evaluating a noise-canceling unit, check and see if the company has considered this in their design, and if possible try the headphones on to see if they are a good personal fit for you.
That’s it. The four considerations above can help you find a great set of active noise-canceling headphones for yourself. There isn’t necessarily a “best” noise cancellation set of headphones, all you need is to find a product that works best for you persona