About Noise Cancelling Headphones

Noise cancelling headphones are becoming increasingly more common as the technology improves and they become more affordable. For people who have never owned noise cancelling headphones you’re about to be amazed. Now you can enjoy your music even in situations where there is a lot of background ambient noise and you don’t even need to turn the volume way up to do it.

How noise cancelling headphones work

Noise cancelling headphones work using two methods. One is passive noise cancellation. Essentially what this involves is simply preventing ambient noise from entering your ear. Most headphones will do this to some extent.

The other method is active noise cancellation and this is what makes noise cancelling headphones so different to standard headphones. You’ve probably heard that sound travels in waves. These waves are like waves in the ocean as they have both a crest and a trough. Instead of travelling through water, sound waves travel through air and differing waves have differing heights and speeds. The way noise cancelling headphones work is to measure these sounds waves from the ambient noise present around you and then create a opposing sound wave which will cancel them out. This works most effectively for lower frequency sounds which makes them perfect for planes and buses. They can also be good in small apartments where people are sharing the same space with you.

How noise cancelling headphones are designed

As you may guess from the description above, noise cancelling headphones require a few components that are not usually used in headphones. These include microphones (these measure the ambient noise that needs to be cancelled), a processor (which determines the required cancelling signal) and batteries (which are required to power the processor).

Like other types of headphones there is the option for on-ear, over-ear and ear-bud models. As the name suggests on-ear headphones sit on your ears. They aren’t the best for noise cancellation because they aren’t very effective at passively cancelling out noise. Over-ear headphones cup your ears creating a seal which blocks out ambient noise very effectively while ear-buds sit in your ear and also are good at passively blocking ambient noise.

The biggest advantage of ear-bud models though is that they are very light weight, fit into a small pouch and can be easily carried around when travelling.

Choosing noise cancelling headphones

So what factors should you look at when choosing noise cancelling headphones? In our opinion you’ll want to consider the following:

Brand – Brands become popular for a reason and usually it is because they offer good products. The most common brands you’re likely to see are Bose, Sennheiser and Sony.

Construction quality - As you will be carrying these around you’ll want to make sure that they are sturdy and won’t break easily. Surprisingly, some brands are not as strong as you would hope.

Size – Choose something that won’t be too heavy or take up too much space.

Cost – There are many types of headphones available with widely varying costs and like most things it is a trade-off between performance/quality vs price.

Noise-cancellation percentage – This measure can be used as a guide to how effective the headphones are at cancelling out noise. Most range from 70% and upwards.

Amount of hiss- Some noise cancelling headphones do have a slight hiss when turned on. However, when music is on this generally isn’t noticeable.

Additional features – Sony’s MDR-NC22 and MDR-NC33 models feature a monitor button which makes it easy to stop your music so that you can hear what is going on around you. They can also operate as normal headphones when switched off or if you run out of batteries.