It’s International Noise Awareness Day on Wednesday, so treat your hard-working ears to a rest, courtesy of some noise-cancelling headphones. Experts agree that hearing damage can occur at levels as low as 85 decibels. A sobering thought when you consider that personal stereos and MP3 players are capable of producing sound of more than 100 decibels. Not only do noise-cancelling headphones let you enjoy your music at lower volume; they also reduce the annoying noise pollution you produce.

Noise-cancelling headphones work by listening to ambient sound around you, then “reversing” it electronically and blending the “antinoise” in with the music from your MP3 player, phone or portable video player. The theory is that the unwanted external noise is cancelled out, leaving just your music in your ears.

In practice they don’t work flawlessly: the tiny microphones mounted in the headphones that pick up outside sounds aren’t perfect; nor is the circuitry that drives them. And all that clever sound-processing affects the music itself, which can sometimes sound mushy and unnatural.

By their nature, then, noise-cancelling headphones are a compromise, giving the biggest benefits when the clamour around you is distractingly loud. And despite the claims made for them by manufacturers, we found the term “noise-cancelling” something of a misnomer – these headphones are better described as “noise-reducing”. Don’t worry about not being able to hear anything when you put them on – the outside world will always be there, just with the background din reduced.

That’s not to say noise-cancelling technology is a waste of money. We found that in many situations, especially when there’s a continuous drone that doesn’t change much in pitch, they were highly effective. Even if you don’t want to listen to music, simply putting them on and powering them up on a bus, train or plane journey can damp unwanted background noise.

Don’t get confused between noise-cancelling headphones and “sound-isolating” earphones. The latter use tightly fitting in-ear buds to cut noise, instead of relying on fancy electronics. They can work well – especially if you spend more than £100 on good-quality models (brands such as Shure and Etymotic are usually reliable) – but they need to be worn inside your ear canal, which some people find uncomfortable and claustrophobic.

Electronic noise-cancelling systems have problems of their own. The audio-processing circuitry takes up space – sometimes inside the headphones but often in an inconveniently dangling box. And you’ll need a battery to power it, adding bulk and weight – the last things you want on portable products. Worse still, some designs (of those featured here, the Sennheiser PXC 300 and Bose QuietComfort 3) simply stop working when the battery is flat: a real drawback on long journeys.

Happily, as our tests show, the latest noise-cancellers are mostly light, power-efficient and sonically impressive, as well as being more affordable than previous models – you no longer need to be a paid-up member of the jet set to afford them.

In a silent environment, none of them approached the fine sound available from a good pair of normal headphones such as Sennheiser’s superb PX 100 (£30). But when you are sitting inside a National Express coach or in BA cattle class, the balance shifts, making them all worthwhile purchases.

There were differences in comfort, wearability, portability, ease of use and sound quality – not to mention widely varying effectiveness at noise reduction. The weakest made little more than a dent in background clatter, whereas the best cocooned the user in a world of calm. And if International Noise Awareness Day weren’t approaching, that might be something worth shouting about.

JARGON BUSTER

Earbuds
Small headphones that fit inside the ear
Noise-cancelling
Electronic sound-processing that reduces background noise. Also called active cancelling
Passive cancelling
Physical designs that help to shut out external noise, such as tight ear pads or in-ear seals. Also called noise-isolating

JOIN THE FOLD
Sennheiser PXC 300
Typically £130, or £80 from www.amazon.co.uk
Brilliant doit-all design and the best all-rounder

The PXC 300s are light (2.3oz) and, within seconds, fold smaller than a pair of sunglasses. Despite their diminutive dimensions, these slimline phones get superb battery life (70 hours) from two AAA batteries. The small earpads cover the ear snugly and offer good sound insulation, but switch on the cancelling and the PXC 300s work almost as well as the most expensive models on test. The sound is fine too, with a smooth and sophisticated quality that lacks only a little detail compared with the best here. While the cable and remote control can get tied up in knots, it’s a small trade-off for a wonderfully light headset that’s comfortable even on long-haul flights. Neat and pocketable this system may be, but it’s big on performance and built to last.

FLYING HIGH
Sennheiser PXC 450
Typically £230, or £180 from www.disking.co.uk
Superb sonics, but the bulk will deter some

These flexible audiophile headphones could have been made for business-class travellers. Noise-cancelling is the best on test, taking loud 747 drones down to subtle murmurs, with a “talk through” button that lets in outside sound – handy when asking the stewardess for another gin and tonic. The silky earpieces sit firmly, although the vinyl padding gets sweaty after a few hours. Sonically the PXC 450s are detailed, smooth and spacious-sounding. They’re also large and heavy (at 8.5oz), and a single AAA battery gives just 15 hours’ playback. Although too bulky for the gym or park, they are a first-class flying companion.

SOUND STYLE
Bose QuietComfort 3
£275 from bose.co.uk
Stunning performance at a premium price

Forget inline battery boxes and fiddly buttons. The fuss-free QuietComfort unit has everything built in, including a rechargeable battery giving about 20 hours of efficient noise-cancelling. The lightweight (5.6oz) headset is beautifully built and feels as though it will last the distance. It’s supremely comfortable too. The QC3 seals out noise surprisingly well, but power it up and it reduces noise further still, cutting whirrs and hums nearly as effectively as Sennheiser’s super PXC 450. Indeed in some ways the Bose sounds even better. Beautifully built, easy to use and impressive to listen to, the Bose almost justifies its huge price tag.

INSIDE JOB
Sony MDR-NC22
Typically £70, or £50 from www.amp3.co.uk
Affordable quality in a compact package

Beautifully made yet light (1.4oz) and small, the most portable phones here show surprisingly few compromises. The noise-cancelling module gives 45 hours’ playback from a single AAA battery, with a mute button to let you converse without removing the earbuds. Properly installed, these release a flood of fine sound, boasting bass equal to the Bose and treble that is clear and atmospheric. The noise cancellation also works well, although it adds hiss that can sound intrusive in quieter surroundings. You might have to experiment with different sizes of rubber isolator to get the earpieces fitting snugly. Overall, a well-made combination of convenience and sound quality.

PLASTIC FANTASTIC
Goldring NS1000
Typically £150, or £135 from www.quantumelectronics.co.uk
Hi-fi but low comfort

Smaller and (at 6.5oz) lighter than the Sennheiser PXC 450, the Goldrings are easier to carry, with a single AAA battery giving about 40 hours’ playing time. Large earcups and the active noise reduction work together to exclude the outside world almost as effectively as the Bose. The NS1000’s electronics are slightly hissier than the other full-sized designs, although this becomes inaudible when music is playing. The strong bass performance makes these headphones ideally suited to rock or dance. They were the least comfortable of our selection but still provide much of the performance of pricier designs for less money.

Reviews by David Price
Prices include Vat but not delivery

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