Customer Ratings & Reviews

These Sennheiser CX 400BT True Wireless Earbuds sound superb! The thing that sets these earbuds apart from a lot of other 'True Wireless' earbuds is the way in which the associated app integrates with the 7mm dynamic drivers and the built in equalizer. I've tested out many different earbuds in different price ranges, and so far, Sennheiser have the app/earbud integration spot on. When I first loaded the app, it has a familiar look and feel to other audio brand apps. However, the equalizer actually put a smile on my face as I configured the sound to my liking, and aurally, the differences were night and day from 'Neutral' to my 'Custom' setting. The bass became deeper, the highs gained clarity and the mids were boosted (I tend to set my equalizers in a pseudo 'U/L' shape for my optimal listening choice). It really heightened my impression of these earbud instantly. Within the app you can also set up what you want the touch sensitive buttons to do, be it answer calls, volume up/down, track forward/back etc to your liking. You can also check on the charge state of the earbuds from here as well. The touch sensors on the side of the earbuds are very sensitive, so you may end up turning your music/sound source on and off a couple of times while placing them in your ear. Also, for note, they do not have a sensor to pause your music when you pull them out of your ear automatically. As soon as you pull them out of the case, assuming you've already paired them, they almost instantly pair to the last source they were paired to. It's seamless and very quick indeed. An audible prompt is played in each earbud. The key to a good sound and decent bass response is a good seal on your ear. There are 4 sizes of tips included, XS/S/M/L. I found that the 'M' were slightly too small for my ears, the seal didn't maintain the bass presence that I wanted, switched to the 'L' tips and they completely sealed my ears, producing the bass tone I was expecting. However, that 'L' size did end up making my ear canal ache after a little while. Still playing around with the tips for a perfect fit. Battery life, I've experienced pretty much what is suggested by Sennheiser which is over 6 hours playback time which is good. You can gain a further 13.5 hours of charge from the case, for a total of 20 hours or so of playback time, before a full recharge is required. As for the fitment, I was skeptical at first on how these were actually going to stay in my ear, but with their 'twist to fit' style design, they actually lock into place in your ear very well, and shaking my head around didn't phase these earbuds at all. Tapping the right bud 1x allows you to access a voice assistant. Tapping the left bud 1x will play/pause music, or answer/end a call. When answering a call, speech is optimized, offering a nice clean/clear connection without any distractions. Worked flawlessly for me. In summary, these Sennheiser earbuds sound superb, especially when used in conjunction with their app! They are not the loudest, or deliver the most extreme bass you've ever heard, but they do pack a nice strong punch, with a definite 'sophisticated' sound to them, absolutely worth their price point!

I've had these for a while and used them a lot. They stand up to the hype the manufacturer says about them. Strong battery life. Totally easy pairing on multiple devices and platforms. They seem to me to be really sensitive to sound to the point I find myself lowering the volume on my device (a great problem to have).

I was really impressed by great this Sennheiser - CX 400BT True Wireless Earbud sounds with a Great bass not overwhelming so you can enjoy your music . Not to use for a rainy day or at the gym it’s not waterproof but it’s sounds great with a Cool sound app !

TL;DR: Pros: USB-C Charging Case Great fit Great sound Great Case Form Factor Great App / Sound Control Volume control on the earbuds! Cons: Charge light on the back by the charging port Have to press a button to see charging status No Side-Tone / Hear Through Longer Version: Let me start off by saying that I use a lot of wireless earbuds and I’m very picky. With these, you aren’t getting some features (read: cost savings), so I won’t hold it against the product, but will note how some things could be different. To start, these don’t have a hear-through mode. It’s where you can hear the outside and people talking, along with the tunes. If these had it, it would be insanity. These earbuds come with, like all, different size rubber pieces to fit different ears. For me, the default one worked without any issue. The first thing I do is charge anything that needs to be charged before I get on with using it. I noticed that the ‘full’ light is right by the charging port, not on the top or front for easy viewing. The charge light was green in about 30 minutes and ready to go. The instructions included a QR code to get the appropriate App for my S10+, so it took away the guesswork if Sennheiser had multiple Apps out there. When you put your earbuds in the case, there’s no indication that they are charging. You have to push a button by the light to see; amber = charging, green = full. I bet there’s a red light when the case is low, but I never saw it. Paired these up fast by holding both ears and away I went. Rock, Reggae and Hip Hop. The sound tuning gives a few options. Move a dot around a sine wave (of sorts) until you hear what you like, or use up/down sliders; I went with the wave to adjust the sound. Great highs, great lows and good bass. I was sold. I went for a bunch of walks as I normally do and typically have some audio cut out with other earbuds. The Sennheiser had none of the drop-outs and there was just uninterrupted music. The earbuds didn’t move around at all, which is awesome because my other ones do Of the past 3-4 brands that I’ve used over the past 2-3 years, I like these better than other earbuds that I have and they’ve become my daily buds. My only wish, is that there was a hear-through mode - but if they do have another version of these with it, I may jump over to those.

Strictly for sound quality alone this is a steal for $100 (same drivers as the Momentum 2's), bought mine when it was $50 more, using Spinfit CP-360's with these.

Actually is my first earbuds and I’m really impressed... great sound and quality is awesome. I use it while operating excavators and front loaders also while I run and work out.. and yes I recommend it. The calls in an out really cristal clear sound

The Sennheiser CX 400BT earbuds are wonderful. The audio is great, they look stylish and more importantly, they’re comfortable. The audio Sennheiser is known for making great audio products, and this is no exception. The sound quality is excellent, and can be adjusted if you download the Sennheiser Smart Control app. The wave setting is a little strange and buggy, but the regular EQ should easily allow you to adjust bass, mid and treble frequencies to your liking. I wish there were presets to be honest. I also want to mention that I don’t hear any audio artifacts that can be common with Bluetooth earbuds. Comfort I personally have an issue with the silicone tips on most earbuds. They either itch or become uncomfortable quickly, this includes the Galaxy Buds by Samsung. I’m happy to report that the Sennheiser silicone tips don’t bother me at all, so I’ve finally found a pair of wireless earbuds I can actually use; without going crazy. The design They look a little boxier than the Galaxy Buds. They look like two boxes in your ears, but the shiny Sennheiser logo gives them a tiny bit of identity. The charging case is also significantly boxier, but it is extremely light. Much lighter than the Galaxy Bud case. I got it in black and it actually looks pretty cool. Connectivity They connect quickly to my Samsung S20+ and pairing was not an issue. So far, I’ve not experienced any dropouts or other issues while using them. They also do a decent job at phone calls with its built in microphone. Battery life There’s no charger included, and the USB-C cable is very short, so you probably have to use your regular phone charger and cable when it needs a charge. You get about seven hours of continued use, plus another 13 hours, thanks to the charging case. That’s a total of 20 hours of use before having to charge, which is not bad. Criticisms Be careful if you use these for exercise or outdoors, because they’re not water resistant. That should be a standard these days, so plan on using these under dry conditions. They’re also noticeably more expensive than the water resistant Galaxy Buds, not that there aren’t any other earbuds in this price range. They’re still much more affordable than the Momentum 2 earbuds, also made by Sennheiser. If you’re looking for earbuds that sound great, feel comfortable and last all day, you can’t go wrong with the CX 400BT earbuds!

This review is for Sennheiser CX 400BT earbud headphones in the box: Sennheiser CX 400BT earbuds USB C charging cable Sennheiser CX 400BT charging case in matte black silicone adapter sets in 4 sizes (including the one already installed quick guide thoughts and impressions: with many options in the market, these earphones offer superior and crisp sound, a very battery life where you get 7 hours of play from the earbuds, and another 13 hours from the battery case charge, the app is simple yet efficient and offers a ton of customization for the touch controls on the earbuds. the case doesn't look super fancy but its decent looking and fits in almost any pocket. pros: - very good sound quality and volume - USB C charging cable instead of Micro USB - great battery life - led light indicator on the case with 3 option to show battery levels: green, orange, and red - led light indicator on each of the buds to show connectivity status - compatible with both Android, and I OS - earbuds auto shut off when placed in case and start charging - case build is sturdy, not flimsy and it will withstand being in pants pocket if thats your preference. - Bluetooth 5.1 low energy connectivity which enables the high battery life. - the silicone attachments allow for fit with any ear size. - highly customizable smart control app. - earbuds are not heavy on the ear - works well with Google assistant Cons: - no noise cancellation - no IPS rating therefore they are not suitable for workout and I wouldn't get them wet. final thoughts: the Sennheiser CX 400BT earbuds have superior sound and very comfortable for extended every day use. the long battery life frees you from worry, and the case offers a sturdy storage and charging option. I wouldn't use them in the rain or when working out though since there is no IPS rating, and they do not offer noise cancellation so I wouldn't use them if I wanted to isolate from the outside world noise.

These ended up costing me $99. They were originally $199 and on sale for $129 the day I bought them and then a few days later the priced changed to $99 and Best Buy did a no hassle price adjustment. Sound quality is tremendous, fit is excellent and BT range is excellent. Sound isolation is so good that you won’t miss ANC, but, it really needs sound transparency added because you’ll probably find yourself pulling one out of your ear to have a conversation with someone. I’d like to see a better app with more frequency bands on the equalizer, better water resistance, and a QI wireless charging case. Yes, the MOMENTUM model has that, but those cost $299 and the CX400BT have the exact same audio components.

Good range, sound quality, and battery life. Only ran out of charge on me once but I usually don’t have to even think about it. There is an app that allows you to customize control inputs. Two downsides to this item: 1. The left earbud DOES NOT work independently of the right earbud. 2. The earbuds have a touch-sensitive surface for controls. Any touch will trigger the control, even setting it down which can be a little annoying as the touch-sensitive surface is the only flat surface on the earbud.

Sound and fit for earbuds are not universal as we all have preferences and unique physical structure. As a 63 year old dude, there was a time when I liked my music loud with a bit of a punch from bass frequencies. My ears have progressed from audiophile to audiopile in many ways. Yet I still LOVE distinct, comfortable sound with occasional world go away and wrap me in sound times. Got these on sale and for frankly less than a Franklin (plus tax) these things are WONDERFUL! Clear. Precise. Balanced and tunable a bit with the app. From instrumental jazz to splendid, rich acapella vocals, these do the job very well. While I have yet to test the longevity, it will happen soon as I take an over six hours considering gate time, movies and music filling it out, or so I hope. At moderate levels, it seems the reviews assure me this will be accomplished with success. I own Bose, Jabra and Schoche brands and each has a signature sound. The transparency of sound, to me is the best in the CX 400BT. As for the fit? My ears work well with the ones that come attached and with a little downward pull on the lobe as I insert them, seal very well. The din of outside noise is there but significantly reduced to a nonissue against the music. Not noise cancelling levels, but MUCH better than an airplane jet roar unfiltered. A touch of the right or left, depending upon what you desire works well for me and can be configured to your liking, one touch, double touch even triple touch and long touch. Left and right touch sequences configured to do different things if you wish. After a short bit of time (two months), I am enjoying the absence of the cables that riddle my Bose SoundSports and the Jabra. I do like that I can pop a Jabra out of my ear and they will just hang there as they are over the ear wires. I was on my second Bose as the first one lost the power button as the rubber ring that held it in slowly broke loose. All my Jabras still work well, but the price point and Sennheiser quality made me try them. Not disappointed. Oh and the very small charging case is a nice touch as well. Easy to store and charge headset alone or plugged in via USB-C. Nice touch. Excellent for the sale price.

The fit on these was the deal breaker. The sound is very unique if you have not any Sennheiser products before. The highs are nice, but do fall apart at higher volumes. The detail and sound of the mids are detailed, and forward, but not over bearing. The bass is very accurate. They create a sound stage that is very reminiscent of over the ear headphones that I have not experienced with other in ear, ear buds. That fit though. These fit firmly, and securely in your ears. This is were I had issues with just the overall size of them, was to much. Not from weight, but the actual circumference of them. After two hours, I would have to take these out, and after about an hour, I definitely started paying attention to the tension on my ears, instead of the music. Not a fan of the lack of resonance with the bass in these. Although I feel like they are more Natural sounding all around, I just kept hoping them to be more Impactful. I never had a Wow moment with these. The sound from these is very particular, and not for a lot of music genres. Loved the sound, even these do not provide enough Punch on the low end for me, but the deal breaker was the fit. If you can catch these on sale, they are worth a listen if you have never heard Sennheiser products before.

I bought these for the sound and fit and have not been disappointed. I have not had any issue with them working their way out of the ear canal while exercising or just a long walk. They are also very comfortable. The sound is much better than my previous Beats partially because I think that they fit so much better. I like the equalizer that comes in the app. Allows me to customize the sound to the type of music that I'm listening to. You can add multiple presets for this which makes it super east. Really glad I made the purchase.

These Sennheiser Wireless Earbuds sound wonderful and the battery life is good. I also like the fact that you can also download the app in order to customize the sound. If you are on a budget shopping for great sounding wireless earbuds, I definitely recommend these for the sound alone. Also they do come with 4 pairs of ear tips (xs, sm, m, l). Just know that these wireless earbuds do not have anc or wireless charging. They did stay in my ears until I started chewing. Bestbuy is selling these earbuds at a great price.

Best earbuds for pure music listeners. You can rock these earbuds to listen to music in the gym, on the streets, and at home. But that's all you're gonna be able to do. Listen to music. Now the listening experience is amazing,, very balanced and pronounced sound. But there's no ANC or any sort of mode that let's you pulls im the sounds from you're environment so that you can hear your name being called or avlid getting ran over. Yes, you can all your touch controls for controlling volume and playback, and controlling voice assistants, but that's it. These don't have that tight of a fit for my ears, so readjustments are needed when being active. They stand out from my ears because they're not so small, the case is on the larger side, it's a sturdy plastic (feels cheap compared to other earbuds in price range) and doesn't have wireless charging. If you're looking for earbuds just to listen to music to, or watch movies privately, and don't need anything else, these are the best sounding ones. They comfortable thanks to them being lightweight, sound great, and have a good battery life.

Great sound stage and fantastic battery life. Comfortable and stays in the eae nicely.

I bought these wireless earbuds on sale. A very great bargain. The sound quality on these earbuds is excellent, very clear. I could hear all the details that I have been missing out on my old headphones. The bass is quite good, and with the built in equalizer, you can easily customize the sound to your liking via the free app from Sennheiser. In addition, they're stylish too. The only con with these earbuds is the comfort/fit. If you have ears on the smaller side, these headphones may be a little uncomfortable and cause some pain since your ears are somewhat stretched for a time because of their slight bulky size. But they do provide an awesome seal, thus providing passive noise cancellation. Otherwise I would have given them full 5 stars. If you buy them, you will NOT be disappointed by their performance, but rather amazed.

Really impressed overall with the clarity of these earbuds. I mainly listen to purchased music through iTunes and podcasts and am happy with what I hear. Be sure to download the app and adjust the EQ, as they definitely come more alive when you add some bass. The bass response on these earbuds are actually quite surprising. They’re obviously not going to shake your ears but the LFE notes are quite clear and provide satisfying sound. It sounds like good bass even without the feel of good bass. There is no sound pass through on these and is probably the only thing I wish I had. These fit quite snugly in my ears and I have to take them out to have a conversation with someone, just pausing the music isn’t good enough. I’ve used these extensively while cutting my lawn (push mower) and they’ve never threatened to fall out, which I’m very pleased with. The touch controls work nice enough and the surface area is large enough to get a successful touch/press the first time, most of the time. I also like that these are a bit larger and are easy to take out or adjust without activating the touch controls. Overall, highly recommended. I was able to pick them up for 50% off. Not sure how often that sale happens but this was in late March.

Comfortable to wear. Sound is acceptable but not the quality of a more pricey set lime the Dr. Dre Powerbeats Pro. Pairs very easily and quickly. Earbud controls are quirky but gets a little less quirky with time.

Fantastic sound quality from the earbuds themselves. The head of the earbuds does dig in to the ridge of the ear, I would have preferred to have a more naturally tailored form instead of the bulbous housings provided. As far as the carrying case is concerned, it feels very lightweight and cheap for the cost, particularly the upper shell. The black matte does look nice though, and the battery hasn't died mid-use yet. For the price point, they're a solid 4/5 stars. The overall design and case could be improved, but the battery, sound, and Bluetooth quality are exceptional - and that's all it's really meant to have.