Noise cancelling headphones test

Acoustic Authority iRhythms A9900

Sensitivity: 119dB
Impedence: 32ohms
Response bandwidth: 20-20,000Hz

Price: £39.99, soon to be available.

The A9900s are the cheapest set on test here, coming in £10 less than the Sony set. Acoustic Authority are a relatively recent entrant to the audio market, but the company has already impressed us with its iRhythms iPod speakers. Can this set of portables work the same magic?

If nothing else, they're sure to make you stand out on a crowded commute, being coloured in a bright iPod white. Whilst they surely provide better sound quality than Apple's ubiquitous earbuds, they're far less subtle in appearance.

The major downside that these things have is that there is an integrated volume control on the headphone wire. We are firmly of the opinion (although you may differ) that such controls are very bad things. Not only do they add weight to the cord, creating a pendulum effect, but the circuitry is primitive - simply a variable resister impeding current, which in turn can lessen the sound quality.

Technically, these ought to sound better than the Sonys, with a larger response width, although the impedence is fully a third higher, meaning they will take more power to drive, draining your battery life.


Feel and fit: The A9900s are quite big, even with the extendable headband compressed to minimal. If you've got a small head, you may find these utterly unusable. They do have the benefit of a very cushy leatherette ring around the earphones, which makes them pretty soft and comfortable to wear for long periods.

They're solidly constructed out of white plastic, and this does make them pretty heavy. Because they're quite big around the headband, the only pressure is really on your ears, which is quite a weird sensation. On the whole, they're fairly comfortable, just slightly odd to wear.

One bonus in this set is that there's no extra bump or dongle for the noise cancelling circuitry - the AAA battery plugs straight into the side of headphones.

Noise cancelling: Unfortunately, the cancelling on this set was the worst out of the three pairs we tested. The inverse noise had next to no effect on voices and did merely an adequate job on ambient noise. However, it gains some extra (passive) cancelling through having padded earphones that do a decent job of blocking some extra noise.

The characteristic hiss of noise cancelling headphones is greater on this than on the Sony, and a little too noticeable for our liking.