Sennheiser CX 400BT Review – Cheap True Wireless & Great Audio

Sennheiser CX 400BT Review – Short words

Sennheiser CX 400BT review: Although the design is not as luxurious as Jabra Evolve 65t. The charging case and earbuds use almost all plastics, so it’s lightweight and easy to portable. However; the sound quality is nearby to the Momentum True Wireless 2. Hence; If you focus on the sound performance without caring about other features, the CX 400BT will definitely not disappoint.

Sennheiser CX 400BT True Wireless Earbuds Review

Sennheiser CX 400BT

True wireless earbuds, passive noise canceling, Bluetooth 5.1, ergonomic design, 7 + 13 hours of playtime, built-in EQ, Voice assist (Alexa/Siri/Google), customizable touch control


Before the Sennheiser CX 400BT review, the previous model, Sennheiser Momentum True Wireless 2, was highly successful in the sound quality and noise cancellation features. This makes the Momentum True Wireless 2 is one of the most popular wireless earbuds. But the price is quite high (above $200), so it may be difficult for many people to make a decision.

That’s why Sennheiser makes a decision to release the more affordable wireless headphones, the Sennheiser CX 400BT True Wireless. With uses the same audio drivers as the MTW2 to keep the sound quality intact, but with a few canceled features. go in order to be able to make the price lower.

The Sennheiser CX 400BT also comes with smart touch control and is comfortable to wear. Plus with a continuous long life of playtime of up to 7 hours on a single charge. Moreover; the charging case gives a battery life of up to 20 hours.

Sennheiser CX 400BT True Wireless Earbuds – The Material and Design

Sennheiser CX 400BT review

The Sennheiser CX 400BT is a nifty and nice design, but the design reduces the cost of some materials for the affordable and cheaper than Momentum true wireless 2. The case is small-sized and light because the material is almost all plastic. The case’s cover is a good tight.

The back is located with an indicator light, a USB-C port, and a pairing button. You don’t worry about earbuds that are easy to fall out of the case due to the case and earbuds being attracted together by magnets.

These wireless earbuds from Sennheiser are customizable touch control via the Sennheiser Smart Control app for iOS and Android. The body of the earbuds is also, is made of plastic too.

The case’s size is 59 x 33.8 x 42.3 mm and its weight is 49 grams. Personally, I feel it’s quite thick, but at this size, it still can be put into the pocket, easily.

How Using the Sennheiser CX 400BT?

Sennheiser CX 400BT True Wireless Earbuds Review

The Sennheiser CX 400BT supports Bluetooth 5.1 connectivity, which allows for much less signal delay. As I mentioned above, the CX 400BT does not come with an active noise-cancelation feature. However; for the wearing, if you choose the right fit ear tips for your ears, the outside noise is almost hardly heard. That is the design of the great earbuds for blocking the outside sound. How wearing earbuds is correct? Once you insert the ear tips into the ears and twist the buds forward slightly. It will make you feel secure and fit your ears.

Don’t worry about whether the ear tips fit your ear. The Sennheiser provided 4 different sizes of ear tips, XS/S/M/L. The default is M. So you can choose one of them that surely fits your ears.

The app allows customizing EQ preset for more amazing sound quality.

According to Sennheiser’s recommendation, should download and connect to the Smart Control app. Then put both earbuds into your ears and touch and hold to enter pairing mode. After that, the CX 400BT TW is shown in the list of Bluetooth devices and is ready to use immediately.

With the app, users can additional settings, easily. For example; shortcut setting (individually left and right), play, pause, voice assistant, and EQ setting.

One obvious drawback is the CX 400BT, which can’t auto-switch devices, users must disconnect from previous devices before connecting to a new device. Even if the device has been connected before.

So if you want to swap between smartphones and laptops, you have to disconnect from the smartphone first before connecting to the laptop. While its main competitor as Apple AirPods has no such issue.

How well the sound quality of the Sennheiser CX 400BT can do?

True wierless earbuds under $200

For a couple of days for testing the Sennheiser CX 400BT, they are truly wireless earbuds that offer very good sound quality, and most importantly they are the best wireless earbuds under $200 (may sometimes be down to $100 up to promotion). The sound’s detail is soft and deep, which is the style of Sennheiser. Even though the price is lower than the MTW2, the sound quality does not deteriorate at all.

How about the call quality?

When it’s come to the call quality, I give an Intermediate rating. Because the noise-canceling is not so good, especially you talking in a loud environment for example; on hard traffic pavement or in the subway. That makes sometimes I can hear my friend’s voice not clearly.

How long of battery life that CX 400BT can?

How well of the playtime that CX 400BT can do? I am very satisfied with the battery life of the Sennheiser CX 400BT. I didn’t take the time exactly, but overall it’s around 6 to 7 hours or a little more. Plus with the charging case, these wireless earbuds can be running up to 20 hours or maybe a bit more too. Another impressive, fast charging, for the full charge take 1.5 hours, wow!

On the back’s case is placed a USB-C slot and a small button for checking the battery status. If the yellow light, means charging, and the green light means it’s full charge.

Compare Sennheiser CX 400BT to Other Wireless Earbuds

Sennheiser CX 400BT Vs Sennheiser CX True Wireless Vs Sennheiser Momentum True Wireless Vs Audio Technica ATH-ANC300TW Vs Tozo Crystal Buds

Sennheiser CX 400BT True Wireless Earbuds Review

Sennheiser CX 400BT True Wireless

Specs: in-ear, dimension: 2.32″ x 1.33″ x 1.67″, weight: 0.42 ounces, driver: dynamic 7mm driver, total harmonic distortion: <0.08% (1kHz / 94dB), Bluetooth 5.1, codec support: AAC/aptX/SBC, app: Smart Control app
Features: true wireless, battery life: 7 hours (single charge)/20 hours (with charging case), customizable touch control, ergonomic design, OS compatible: iOS/Andriod, voice assistant, automatic on/off
In the box: CX 400BT True Wireless, charging case, silicone ear adapter sets (in size XS/S/M/L), USB-C charging cable


Sennheiser CX true wireless review

Sennheiser CX True Wireless

Specs: in-ear, dimension: 2.3″ x 1.3″ x 1.6″, weight: 49g (both earbuds + case)/37g (case)/6g (single earbud), speaker type: TrueResponse transducer 7mm dynamic driver, charging type: USB type C, frequency response: 5 – 21kHz (headphones/ 100 –  10kHz (microphone, microphone: 2 mic beamforming arrays (total 4 mics), battery: Lithium-ion rechargeable (400mAh – charging case)/60mAh (earbud)
Features: true wireless, customizable touch control, extra bass boost, splash-resistant: IPX4, passive noise cancellation, TrueResponse transducer, playtime: 9H (single charge)+ 18H (with case), Bluetooth 5.2 class 1 BLE, code: SBC/AAC/aptX™ support profile: A2DP/AVRCP/HFP
What’s in the box: CX True wireless earbuds, charging case, USB-C cable, Silicone ear adapter sets (XS/S/M/L), user manual & safety guide


Sennheiser Momentum true wireless 2

Sennheiser Momentum True Wireless 2

Specs: in-ear, dimension: 6.69″ x 4.53″ x 1.77″, weight: 12g(2 earbuds)/48g (charge case), Bluetooth 5.1, Bluetooth profile: A2DP/AVRCP/HSP/ HFP, support code: SBC/AAC/aptX™, charging type: USB-C, full charge time: 1.5 hours, frequency response: 5 – 21kHz, THD: <0,08% (1kHz / 94dB)
Features: true wireless, active noise-canceling, ergonomic & lightweight design, sound: natural mids/clear & detailed treble/deep bass, playtime: 7 hours (earbuds)/28 hours (with charging case), customizable touch-control, voice assistant: Google assistant/Siri/Alexa, splash-resistant: IPX4, aptX, quick charge: 15 minutes get 1.5 hours, app: Sennheiser Smart Control app for iOS™ and Android™, warranty: 2 years


Audio-Technica ATH ANC300TW - specs

Audio-Technica ATH-ANC300TW, Model: ATH-ANC300TW

Specs: fit-type: in-ear, dimension: 7.00″ x 3.00″ x 2.00″, weight: 3.53 ounces, driver: 5.8mm with diamond-like carbon (DLC), frequency response: 20 – 25kHz, sensitivity: 106 dB/mW, impedance: 14 ohms, microphones: MEMS type
Features: active noise-canceling, quick hear-through, water-resistant: IPX2, battery life: 4.5 hours (earbuds)/18 hours (with charging case), charge time: 1 hour (earbuds)/ 2.5 hours (charge case), different size silicone ear tips in the box (XS/S/M/L)


Tozo Crystal Buds wireless earbuds - where to buy

Tozo Crystal Buds

Specs: form factor: in-ear, package dimension: 3.35″ x 3.23″ x 1.5″, weight: 3.52 ounces,
Features: Bluetooth 5.3, one-step pairing, true wireless earbuds, waterproof rating: IPX7, dual digital LED battery display, playtime: 9 hours (single charge)/40 hours (with charging case), built-in 4 NC mics, multi EQ modes with app


Sennheiser CX 400BT Review – How about benefits and drawbacks?


  • Great sound quality
  • Comfortable for wearing, not fatigued even long sessions listening to music
  • Long playtime for one single charge (lasts up to 7 hours continuously)


  • There is no active noise cancellation system
  • Unilateral use can only be with the right earbuds
  • There is no automatic switch connection to other devices
  • No wearing sensor

Sennheiser CX 400BT Review – Final Verdict

All in all the Sennheiser CX 400BT review is truly wireless earbuds with great sound quality. Sennheiser’s intention is to provide buyers with quality wireless earbuds at an affordable price. Even though there is no ANC, the design is good noise-isolating with four different sizes of ear tips. Lightweight with almost all plastic material and long-life battery that allows convenience for taking away.

Where to buy Sennheiser CX 400BT?

Sennheiser CX 400BT review
Sennheiser CX 400BT:
True wireless earbuds, passive noise canceling, Bluetooth 5.1, ergonomic design
7 + 13 hours of playtime, built-in EQ, Voice assist (Alexa/Siri/Google), customizable touch control


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