The headphones come into their own where you can plug straight into an existing handsfree or remote control unit

Mobile phone headset upgrade potential; Good sound; Carry case

Bass not so good; Cable options can be inconvenient

“The sound is incredible, but the cost of a lowered price is a bunch of missing features.”

Superb sound quality; Responsive and customizable controls; Highly adjustable onboard EQ

Lacks features for the money; Possible fit and comfort problems

Contrary to the many reviews I read online before purchasing these earphones, they just would not stay in my ears. I tried all the different size tips on them but it didn't seem to make much difference. I've been using the old Apple wired earphones for years as they fit really well for me, but finally made the move to wireless with these and they didn't fit at all. Have switched to Airpods 2 now and they fit perfectly. Otherwise though, the Sennheisers are great. Very light weight, the touch controls are great and easy to use, and the sound quality is excellent. If they fit your ears, you'll be set. If not, they're pretty much unusable. Good luck figuring it out lol.

Sennheiser has a reputation for top-quality sound, and both the Momentum True Wireless and its sequel, the Momentum 2 True Wireless, scored very highly on sound quality when we reviewed them. But along with that excellent sound comes a fairly steep price — $300 is what you’ll pay for these earbuds. Clearly, that eliminates a lot of potential buyers. So the challenge for Sennheiser was to create a set of true wireless earbuds that cost less without sacrificing the biggest reason for buying them in the first place: High-quality sound. Its answer to that challenge is the $200 CX 400BT True Wireless. Their price is definitely more palatable, but do their overall feature set and performance make them a worthwhile investment when you consider how many other excellent earbuds can be had for the same, or similar, money? Let’s take a look. The CX 400BT’s relatively plain cardboard box contains the earbuds, their charging case, a set of four sizes of silicone eartips (large, medium, small, and e...

Superb sound quality; Responsive and customizable controls; Highly adjustable onboard EQ;

Lacks features for the money; Possible fit and comfort problems;

The Sennheiser CX 400BT are no ordinary pair of mid-range wireless earbuds. Their balanced, detailed sound, excellent comfort and myriad of features ensure they stand out in a crowded market.

Great sound, Good app and features, Respectable battery life, Comfortable fit

No ANC, No water or sweat resistance

The Sennheiser CX 400BT is a winner when we talk about the design and the audio performance. The earbuds come with customisable touch controls and they also offer a pretty good battery backup. The only thing we felt was missing was the features like ANC, Ambient Mode and wear detection.

They’re not the most glamorous nor the most distinctive – but Sennheiser’s new CX400BT true wireless earbuds have it where it counts. They sound open and articulate, and if there’s detail in a recording to be extracted, you can rely on them to do just that.

Widescreen; detailed; and quite upfront sound; More comfortable to wear than they look; Great app and good touch-control

Can be excitable with treble sounds; Ordinary battery life; Don’t quite look or feel the asking price

My time using the CX 400BT was very enjoyable. I appreciated all the customizable options and warm sound signature, as well as their flawless connection and accessibility. For $199.95 this is a solid true wireless from Sennheiser, and a sure buy if you’re looking for a reliable pair.

The Sennheiser CX 400BT is a compact truly wireless set with a charging case that is easily held in your hands....

The Sennheiser CX 400BT True Wireless earphones are many things but it’s no question they follow one of the German audio company’s hard-to-remember naming conventions.