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Superior sound. Tailored to you.
Your day-to-day may change but your enjoyment of superior sound
won’t. Powered by Sennheiser’s leading audio technology, the new
CX 400BT True Wireless gives you total control over an exceptional sound experience. With intuitive customizable controls,
long-lasting battery life and a design made for all-day comfort,
they are the ideal, uncompromised choice for people that are
passionate about great sound.
Superior Sound
Immerse yourself in amazing sound quality thanks to Sennheiser’s
unique 7mm dynamic audio drivers and personalize your audio
experience with the built-in equalizer and the Sennheiser Smart
Control app.
Customisable Controls
Manage your music, make calls or trigger the voice assistant with
customisable touch-sensitive technology built into both earbuds.
Codec Support
Enjoy outstanding sound quality no matter your mobile device with our
wide range of audio codec support including AAC, aptX and SBC.
Battery Life
Experience non-stop play time with a 20 hours of battery life – 7 hours
on a single charge and a further 13 hours via the charging case.
Ergonomic Design
Dive into your favorite music for as long as you like with an ergonomic
design made for all-day wearing.
Technical Data
CX400TW1 Black CX400TW1 White
EAN 4044155251753 4044155251760
UPC 615104346901 615104346925
Article No. 508900 508901
General Data
Wearing style True wireless stereo earphones
Ear coupling Ear canal
Connectivity
Supported profiles A2DP, AVRCP, HSP, HFP
Supported codecs SBC, AAC, aptX™
Speaker principle Dynamic
Speaker size 7mm diameter
Speaker frequency range 5 Hz – 21 kHz
Speaker sensitivity 107 dB SPL (1 kHz / 1 mW)
Speaker THD <0,08% (1kHz / 94dB)
Active Noise Cancellation No; only passive noise cancellation
Mic principle MEMS
Mic frequency range 100 Hz – 10 kHz
Mic pick-up pattern 2 mic pick-up for ambient noise reduction
Battery lifespan Up to 7 hrs music playtime with earbuds;
Charging time Approx. 1.5 hrs for full charge; After 10 min
Battery type Built-in Lithium-Ion rechargeable batteries;
Power supply 5 V⎓, 650 mA max; USB charging via
Bluetooth 5.1 compliant, class 1, 10 mW (max)
Up to 20 hrs overall music playtime with
charging case
charging 1 hr music playtime; After 60 min
charging 5 hrs music playtime
L/R earbud: 55 mAh; charging case: 420 mAh
USB-C socket at charging case
Packaging
Content of delivery
Product weight Earbuds & charging case: 49 g (1.7 oz)
Packaging type Hard box
Language on packaging English, German, French, Spanish,
Dimensions product packaging
(L x B x H)
Weight of headset and
packaging (incl. accessories)
Dimensions of outer master
carton (L x B x H)
Number of products per outer
master carton
Total weight of outer master
carton & products
WEEE packaging infor mation
Material of single package
(incl. weight)
Material of outer master
carton (incl. weight)
WEEE Weight (Net weight) 60 g (2.1 oz)
CX 400BT True Wireless earbuds
Charging case
USB-C charging cable
Silicone ear adapter sets (XS/S/M/L)
Single earbud: 6 g (0.2 oz)
Charging case: 37 g (1.3 oz)
Simplified Chinese, Japanese
170 x 115 x 47 mm
(6.7 x 4.5 x 1.85 in)
202 g
(7.1 oz)
279 x 245 x 200 mm
(10.9 x 9.6 x 7.8 in)
12
2900 g
(6.3 lbs)
Paper / Cardboard:
140 g (4.9 oz)
Paper / Cardboard:
448 g (15.8 oz)
Plastic:
2.8 g (0.09 oz)
Plastic:
29 g (1 oz)
07/20 Sennheiser is a registered trademark of Sennheiser electronic GmbH & Co. KG www.sennheiser.com