




🎶 Elevate your sound game—because your ears deserve the best.
The Sennheiser CX 400BT True Wireless Earbuds combine premium 7mm dynamic drivers with customizable touch controls and a built-in equalizer to deliver personalized, high-fidelity sound. Featuring Bluetooth 5.1 and support for multiple codecs, these earbuds ensure seamless connectivity across devices. With up to 20 hours of battery life and ergonomic silicone tips in four sizes, they offer all-day comfort and convenience for music lovers and professionals on the go.






| Age range (description) | Adult |
| Material | Silicone |
| Specific uses for product | Travel, Music |
| Charging time | 20 Hours |
| Compatible devices | smartphones, tablets, laptops, desktops, car audio systems, smart speakers, televisions |
| Control type | Voice Control |
| Cable feature | Detachable |
| Item weight | 0.42 Ounces |
| Water resistance level | Not Water Resistant |
| Frequency range | 20Hz - 20,000Hz |
| Unit count | 1.0 count |
| Style | In-ear |
| Control method | Touch |
| Number of items | 1 |
| Product Dimensions | 5.9 x 3.38 x 4.23 cm; 11.91 g |
| Batteries | 1 Lithium Polymer batteries required. (included) |
| Item model number | CX400TW1 Black |
| Manufacturer | Sennheiser |
| Form Factor | Earbuds |
| Power Source | Battery-Powered |
| Average Battery Life (in hours) | 20 Hours |
| Are Batteries Included | Yes |
| Lithium Battery Energy Content | 55 Milliamp Hours (mAh) |
| Lithium Battery Packaging | Batteries contained in equipment |
| Lithium Battery Weight | 0.45 Grams |
| Number Of Lithium Ion Cells | 1 |
| Item Weight | 11.9 g |
| Guaranteed software updates until | unknown |
L**R
Great sounding when they work
The earbuds themselves sound great! They don’t have noise cancellation but they may as well do as their tight seal means that unwanted sound is greatly reduced. Touch controls could do with some work. Although their position on the earbuds and sensitivity is good, it is quite difficult to change the bindings through the app.Now for the bad bit. They love to ruin your day by not working. They have broken twice on me now and it’s the same problem, the left earbud not outputting any sound. I honestly can’t believe how Sennheiser expected to get away with this atrocity of bad design. This one flaw takes what could have been a great addition to Sennheiser’s lineup of headphones to a dark stain, that to me, ruins their brand reputation. They should be ashamed of this abysmal oversight.That said, their maintenance and customer service team have done a good job with the warranty. The replacement pair came relatively quickly and did work for some time. Not happy with the £5 shipping fee that the customer must foot to make up for Sennheiser’s faulty products, however.Please do not buy this product. I beg you. Please teach them not to release a mess of a product again.Sincerely, a vexed customer.
Trustpilot
2 weeks ago
2 weeks ago