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Sennheiser CX 400BT review

£125.06 View retailers

Test scoreShow Context

Key features
  • In-ear
  • Wireless
Expert review

The Sennheiser CX 400BT truly wireless headphones are Sennheiser’s answer to the Apple AirPods and aim to offer even more. Could they also be a great option for both Android and Apple device owners? There’s a lot of stiff competition at this price point – so our professionals find out if they stand out from the crowd with excellent sound quality, battery life and more. Find out the Which? test lab verdict in our full expert review.

What's included:
  • Pros and cons
  • What are they?
  • How do they sound?
  • What are they like to live with?
  • Is there anything I should watch out for?
  • Is there anything else I should know?
  • Why are these headphones an Eco Buy?
  • Should I buy them?
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Last checked by Which?

July 2022

First reviewed by Which?

October 2020

Released

May 2020

Test results

The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.

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Best Buys and Don't Buys
We have tested 265 headphones and found that there are 46 Don't Buys and 34 Best Buys.
Range of Headphone scores
  1. 10%
    Lowest score
  2. 55%
    Average score
  3. 91%
    Highest score
We'll show you where this model sits on the scale so that you can see how it compares to headphones we've tested
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Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

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