Sennheiser CX True Wireless

With the sweet-spot of affordable true wireless headphones now firmly established at £120, Sennheiser’s new CX True Wireless enter the fray. Looking at the spec-sheet, that is no small feat; the company’s proprietary Trueresponse transducer (found in more premium models in the company’s line-up) features, as does Bluetooth 5.2 with aptx support, a host of EQ optimisations via the Sennheiser Smart Control app and even a neat slider feature, Sidetone, to control the level of audible feedback of your own voice during calls. There’s no ANC on board, but there’s enough here to make us more than a little intrigued.

Brutalist aesthetic

The CX aren’t particularly small or ergonomically shaped. The housings are almost square, weighing 6g apiece (half the weight of an AAA battery), and the neck is on the long side, meaning that even if you downsize to the smallest of the four pairs of eartips provided, those with smaller ears may struggle to achieve a decent or comfortable fit.

The multi-function sensor on each earpiece is also very easy to cover (and thus deploy) while trying to fit them, but once a decent seal is achieved, the functions are customisable and work very reliably indeed. From the box, play or pause is a single tap of either earpiece, two taps on the left bud skips back a track, two on the right skips forward and a long-press of either earpiece increases (right) or decreases (left) the volume. Three taps of the right bud summons Siri on our iphone. Accepting and ending calls is intuitive and works well, aided by the two beamforming mics in each earpiece. It’s an intuitive solution and a useful one, especially when you consider that many buds at this price (and beyond it) have failed to offer on-ear volume control.

Under the bonnet, Sennheiser’s Trueresponse Transducer 7mm dynamic driver takes centre stage. Despite the slightly bulky design of the earpieces those who favour a brutalist aesthetic in their gear will enjoy the squared-off buds, both bearing Sennheiser’s angular but simple S-in-a-rectangle logo. Nine hours of playtime, 27 with juice from the case, completes an interesting proposition – not class-leading, still but competitive.

Slick and intuitive app

There’s no ANC, no transparency feature and no auto-off wearer detection here. However, what you are getting over the older CX 400BT is better connectivity and stamina, IPX4 splash proofing plus Bluetooth 5.2 compatibility with SBC, AAC and aptx codec support for higherresolution listening, not to mention the very slick and intuitive experience offered by the Sennheiser Smart Control app. Here, you can connect further devices, which are then saved in the ‘Connections’ tab. It’s not quite as effortless as multidevice pairing, but once added, toggling music sources is simpler than going in through the Bluetooth menu every time.

You can also play with two distinct and detailed methods of EQ adjustment here (one standard three-band, one a curved line you simply move and shape with your finger), then save them as presets, or select from Sennheiser’s own curated profiles. We keep the EQ levels at neutral, for testing, but it’s worth experimenting.

Kicking off with Bamboleo by the Gypsy Kings, each initial duelling guitar lick is delivered first to our left ear, then our right, with ample space and a good deal more separation than we usually experience through in-ear designs. The hand claps also feel three-dimensional through the treble, if a tad harsh.

Our playlist continues to Gypsy by Shakira, but here we note that the strummed guitars and vocals through the lower midrange are more textured and exciting through our benchmark product for this test, the Melomania 1 Plus. Dynamically, the CX feel a little subdued in comparison, lacking an extra ounce of detail through the rise and fall of each note. The bass weight plays no small part in the issue. It is expansive but a little bloated and not particularly agile, so the overall presentation comes off somewhat lacklustre in terms of dynamic build.

Switching to Don’t Stop Believin’ by Journey, we note that although there’s a good deal of space around each instrument in the soundstage, the treble guitar riff is slightly hard in isolation, which only adds to a confusing mix, timing-wise. Each musical strand seems to have a habit of wandering off a little, leaving us unable to tap our feet in time to the rhythm – even when listening to this classic marching rock track.

The CX buds weigh the same as the CX 400BT, but a few members of the team find the units bulky and uncomfortable to wear after a few hours of testing. The seven extra hours of battery life and new Ip-rating are welcome additions and the in-app features are nothing short of excellent for the level, but when it comes to the sound, we find ourselves scratching our heads to explain the treble harshness, timing issues and slightly flabby bass.