Sennheiser CX400BT

These ‘affordable’ true wireless earbuds are something of a wolf in sheep’s clothing £169 sennheiser.com

hile Sennheiser’s never in any danger of winning the Most Stylish award for any of its headphones, where performance is concerned the CX400BT have almost everything you could realistically hope for. They have the Apple AirPods firmly in their sights while still doing things entirely their own way.

Because this is Sennheiser, they’re flawlessly constructed. Though the plastics used feel (and look) quite hard and shiny, there’s nothing that doesn’t suggest both ‘quality’ and ‘longevity’. And once you’ve selected the correctly sized eartip, their twist-to-fit action means they fit securely, stay comfortable for hours and offer physical noise reduction beyond what the more ‘open fit’ AirPods can achieve.

However, it’s just a little disappointing to discover there’s an all-in battery life of 20 hours here (seven hours in the buds and another 13 held in the case). Many rival designs do better.

As far as sound quality goes, they have nothing to learn from any similarly priced rivals (or quite a few more expensive options, either).

WThey generate an extremely wide, well defined stage, and are as alert to the finest details as they are the broadest strokes of a recording. Combined with well-controlled low frequency presence, ample dynamic headroom and impressive sense of timing and integration, the CX400BT are among the most capable allrounders this sort of money can buy. In fact, about the only area where the praise they deserve is qualified concerns the highest frequencies. They are positive to the point of overconfidence where treble is concerned, threatening to get rather hard and rattly.

The CX400BT are pretty similar to Sennheiser’s pricier Momentums where the user interface is concerned – which is a good thing. There are pretty large touch-sensitive surfaces on each earbud for controlling playback, handling calls or summoning voice assistants. In its ‘Smart Control’ app, Sennheiser has one of the more useful, clean and stable examples of EQ adjustment you can find and some customisation of the touch-control functions too.

Get beyond the rather functional looks (and feel) and the CX400BT are a capable and likeable listen. As far as soundstaging and detail retrieval go they’re as good as anything else around, and they have real talent where the timing and dynamism of a recording is concerned too.