Sennheiser’s CX 400BT is Clarissa's Best Buddy for Work and Recreation

Sennheiser is back with their latest true wireless earbuds, the CX 400BT True Wireless! These are the audio specialist’s latest premium True Wireless Bluetooth earbuds. They deliver exceptional sound quality, optimal comfort and customisable touch controls, as well as providing the best possible listening experience thanks to their ergonomic design and all-day battery life. You can check out the short review and unboxing video I did below!

From the get-go, the first thing I noticed were its aesthetics. I really liked the white and clean look of them. Even though the material of the casing was made of plastic, that didn’t make it lose its premium feel. The size of the earbuds, though on the chunkier side, fit perfectly into my ears. It comes with silicon ear adaptor sets so there’s no need to worry if they wouldn’t fit. I was pleasantly surprised! I felt like the chunky earbuds added to the sturdy feeling of the earbuds in my ear. The overall design of the earbuds is sleek.

Sennheiser promises seven hours of battery life on the earbuds themselves, with another 13 hours in the charging case. I used them through the night to watch lectures and movies without the need to charge. For those who are doing more intensive listening, we can charge a further 13 hours with the small, sleek and compact charging case. The new CX 400BT True Wireless earbuds are designed to ensure you get premium sound wherever you go.

The CX 400BT includes the 7mm “dynamic drivers”. There’s outstanding clarity in the details of most genres and a deep, warm sound stage that is simply a joy to listen to. You can even play with the Smart Control app that offers custom EQ options. I am not picky about my sounds, but for those who are more particular, this might be useful. Aside from the abstract curve that you can swipe around to adjust the tuning, there’s also a more intuitive slider option as well. Pre-sets can be saved with a custom name in the application.

However, it does not feature active noise cancellation. This new and more affordable model only offers passive noise isolation. There is also no transparency mode. Hence, conversations without removing the earbuds are tough.

Overall, I enjoyed the detailed sounds and the dealbreaker was that it was unexpectedly very comfortable, hence I would rate it very positively. The only downside was the chunky feel of it, but I am completely okay with that. The Sennheiser CX 400BT is available in stores at SGD$299.

Rating: 4.5/5

Affordable mid-range TWS earbuds for both work and play. It has detailed sounds and fits comfortably, featuring up to 20 hours of battery life.

Technical Specifications

Driver Size: Sennheiser 7mm dynamic driver
Frequency Response: 5 – 21,000 Hz
Wireless Connectivity: Bluetooth 5.1 compliant
Bluetooth codecs: SBC, AAC, aptX™
Battery Life: Up to 7 hrs music playtime with earbuds, Up to 20 hrs music playtime with charging case
Weight: 49g (both earbuds and charging case), 6g (single earbud)
Dimension: 59 x 33.8 x 42.3 mm (earbuds and charging case)