Why noise cancelling headphones are bad

After visiting the headquarters of Iris last year, a firm that prides itself on creating a set of headphones that will provide your 10, steps a day aurally, one doesn't necessarily have to agree with every aspect of the company rhetoric to accept the idea that our brains are actively looking out for sonic cues as a means of self-preservation, and that by quashing even low-level noises through ANC, our brains are receiving confusing signals, particularly if we're on the move.

It put me in mind of a study carried out on the effects of artificial sweeteners made from aspartame. Here, the brain believes the body is receiving sugar and so releases serotonin the happy hormone , but of course, no actual sugar or calorific value has been ingested. The resulting neurobehavioral discrepancy has been linked to mood swings and even depression.

The inconsistency whereby the brain actively looks for background noise it knows should be there, but finds none, is of course easy to remedy by removing your headphones or at least dialling down the ANC, but perhaps it's worth considering the effects of what we feed into our bodies both nutritionally and sonically and being a little more truthful with these?

A stretch, perhaps, but a suggestion nonetheless. So now that I have explained myself — and in an effort to dissuade the anticipated hate mail — here are some reasons you may very well enjoy noise cancelling, even if I do not: the tech behind noise-cancelling is extremely effective. Furthermore, the anti-noise created by ANC technology is not damaging to your hearing on any level — a truth that has been proven by trusted experts. You do not perceive, on any level, the anti-noise" confirms Oclee-Brown.

We have a whole feature on how ANC works , but essentially, low-level, constant ambient noise is recorded by the headphone, with a little microphone. It then creates and sends out an 'anti-noise' signal from the speaker in the headphone so that it cancels the incoming noise. And this works very well indeed. Secondly, although the chipset, mics, and rigorous testing needed to achieve effective noise cancellation may drive up the price of a set of in- or over-ears, I do not believe sound quality is at all compromised by ANC when it has been done well — even within a price category and against non-ANC products.

Again, I defer to Mr. Third, despite having raised concerns over the potential negative impacts on the health and wellbeing of wearers, I fully recognise the significant health benefits of noise-cancelling. The NHS widely encourages the use of ANC headphones, not just to promote listening at lower volumes and thus protect your hearing, but because noise annoyance is a real health issue. Various studies on hospitalised people with long-term illnesses showed that the effect of a piece of constantly-beeping machinery on a patient's wellness and psychosis could be extreme — and this can be greatly eased with both ANC and music.

Many people can just buy top-brand noise-cancelling headphones, put them on, and enjoy their next flight in peace. This pain can be intense enough that people end up stuffing their expensive noise-cancelling headphones in a drawer as we did or giving them away. Eardrum pain is the least of the problems for some listeners, who have told us they also experience headaches, dizziness, or nausea. And the more powerful the noise cancelling, the worse the problem seems to be.

Sure, you might be able to turn off the noise-cancelling function and make the problem go away, but then the extra money you likely spent to get noise-cancelling headphones will have been wasted. For an explanation of how active noise cancellation works, check out our guide to the best noise-cancelling headphones.

But the brain rules the body, so pain is the result. The effectiveness of active noise cancelling ANC is usually limited to lower frequencies of sound, below 1 kHz. The ear cups of PNC headphones create an airtight seal over the ear, preventing sound from leaking out or coming in, and high-density material like memory foam further dampens unwanted noise.

Active noise cancellation ANC uses a sophisticated system that electronically manipulates external sound to cancel it out. ANC begins with a miniature microphone sampling the ambient noise in your surroundings.

These soundwaves are basically pressure waves that travel through the air at a specific frequency. The microphone then takes the sampled audio and feeds it into the battery-powered noise-canceling system in the headphones. The system then inverts it, producing a signal that is the exact opposite of the original.

And finally, the headphone speakers plays back this opposite signal. When two frequencies or signals are in complete opposition to each other, that means they are in antiphase. And when two signals in antiphase collide, destructive interference occurs. Destructive interference occurs when the highest point of one frequency meets the lowest point of its opposing frequency seen in the left image , thereby canceling them both out.

This contrasts with what we see in the rightmost image constructive interference wherein the two frequencies are identical, resulting in a more amplified signal.

In sum, ANC headphones produce opposing frequencies that cancel out the frequencies of the ambient noise around you, resulting in silence. All these additional mechanisms and advanced technology make ANC headphones stand out when it comes to noise reduction as compared to Passive Noise Cancelling headphones. However, its effectiveness can sometimes base on how well its internal mechanisms were made and integrated into the headphones. In turn, this also affects the overall costs.

In fact, the ANC technology was actually invented mainly for the hearing protection of pilots against the loud sounds of the plane engine. This is why noise-canceling headphones can be beneficial in helping prevent hearing loss and alleviating noise-related stress.

This is particularly important for people with sensitive hearing, and children who are more prone to hearing damage when continually exposed to noise. A pair of headphones that combined PNC structure with ANC technology would provide optimal protection in all scenarios. If you're looking to shield your ears from explosive or high-frequency sounds, PNC headphones are the way to go. Because ANC headphones require some time to identify external sounds and match those sounds, they aren't good at adjusting to and protecting you from fleeting sounds.

However, if you're purely looking for ear protection, you'd probably be better off with protective earmuffs. If you're looking to ward off the constant buzzing of public transportation, busy streets and crowded offices, you would benefit from ANC headphones.

You can significantly reduce your risk of noise-induced hearing loss by listening to music at lower volumes, which ANC headphones allow you to do. It's worth noting that noise-cancelling headphones aren't a good choice for listening to music while exercising outdoors. In situations where you need to pay attention to your surrounds -- say biking on a busy street -- you'll want to follow these tips for staying safe with headphones while running or biking.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice.

Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.