Sennheiser Consumer Audio CX 400BT True Wireless Earbuds - Bluetooth In-Ear Headphones for Music and Calls - with Noise Cancellation and Customizable Touch Controls, White

Of all the audio upgrades I have bought in my life, these earphones were the best $100 I have ever spent.There are only two things I wish were improved or included. First is the battery life. They will realistically give 5-6 hours per charge in real world use. This is from full charge to the devices shutting off from low battery. They charge quickly in the case or even faster with the case plugged in. Still, longer battery life would be welcome. The second is the lack of Adptx HD codec. They only support AAC, SBC, and Adptx LL. The audio quality of these earphones warrants the best codecs and I'm surprised that was not included.With that said, there is little to fault in the sound quality. When I first put them in and paired them, they presented the worse sound I have ever heard from earphones. Even airplane throwaways sounded better. Then I remembered reading another comment about the same thing and stating they needed to be broken in. Being familiar with high end audio I figured I would break them in for two charge cycled. I parked them with my phone and streamed Tidal until they went dead, charged up and repeated. When I charged them up and put them on. I was presented some of the best audio I had ever heard from an earphone. The sound was incredibly detailed, accurate but slightly heavy in the high end. Bass sounded thin but very accurate. This turned out to not be the case. I opened the Sennheiser app and reduced the high end by 3db. That was just what was needed and they smoothed out and sounded very detailed but not hard it edgy like before. As for the bass, I did nothing but listen to several tracks I was extremely familiar with. When the track calls for bass it is there. Tight, controlled, not boomy or elevated as most headsets are, and very deep. In other words they deliver what is in the recording, not equalized to sound bass heavy. The more I listened, the more I heard what an incredible sounding ear buds these are. I did not want ANC. I feel it has its place in certain applications like travel, but I only have these to listen to music. The isolation is very good and minimal ambient noise gets in. Even outside or walking with traffic they seal very well. I hear more audio artifacts from noise canceling that bother me than a little bit of ambient noise. After all, if listening to speakers you hear everything anyway, even in a quiet living room.These are worn often, sometimes 12-13 a day. Phone calls sound amazing and while the mics are not the most noise canceling for cell calls out there, I have only heard a few people afk if I was outside when there was string winds. But all say voice quality is excellent.To get any better audio quality many times more money has to be spent and even in the $400-$500 range I have heard nothing that that is any better sounding. Better than Bose, WAY better than air-pods. This is based on audio quality only. If you MUST have ANC or longer battery life for some reason these will not work for you.If you are looking for unbeatable sound,there is nothing close to these without getting into the over $750 range and up. For $100, these are the audiophile bargain of the year. Will not be sorry if you purchase these.

Let's get the obvious out of the way: these buds are larger than you expect, and heavier, in part due to the 7mm driver (same as the more expensive Momentum line from Sennheiser)... but you won't care about the size or weight, because they just sound so, so incredible.That 7mm driver does make amazing sound, better than any wireless earbud I've tried, and for around $100 at the time of my purchase, this has better "quality sound / dollar" than anything I've tried.But there are some odd design decisions. The touch surface for the control on the outside of the big block is hypersensitive (even a quick touch from my hand can trigger a pause, much more sensitive than, say, Airpods Pro). On the good side, you can control volume from these, but it's a bit tricky due to the sensitivity. For all the audio quality, I found I had to set the volume higher with these than with other earbuds on both iPhone and Windows PC Bluetooth (in Windows, go to Sound in the Control Panel (under "Hardware and Sound"), highlight your headphones, click Properties, and select the Enhancements tab. Check "Loudness Equalization" and hit Apply to turn this on, helps a ton). With the plugs in, your do get good isolation from the outside (so "passive" noise reduction), though of course, you now hear every breath and gurgle from inside your body, as you do with any sealed-ear device. Even with a Bluetooth 5.0 connection (they support up to 5.1) on the PC, BT lag is still present; this is really evident watching videos and, to some extent, on video conferences. The buds stick out from your head, and are heavy, so extended wearing became ear-canal sore, but never really painful. The ear tips are silicone, but less flexible than from other vendors: I usually wear a medium in other earbuds, but it feels a touch large for my ears; the small felt too small. I may invest in Comply Foam for the first time.The buds support SBC, AAC and aptX, which is nice for iOS or Android users. Microphone quality is the usual: it's good enough, but not as good as Airpods Pro, and clearly not the primary focus of the buds. It'll be ok, but expect to have to repeat sometimes, as with almost every wireless earbud out there. Also, I missed the auto-shutoff from so many of the other modern earbuds; these just keep playing when you take them out (luckily, due to the hypersensitive touch panels, I accidentally pause when taking them out most times!).Also, an odd design choice means that the "power pads" where the buds connect to the terminals in the case is just rear of the earplug; this puts a ridged surface directly touching one of the folds of the ear. If you push the earpiece all the way in, you are putting the one rough surface directly against your ear. Sennheiser could have easily put this on, say, the rear-facing portion of the block and let smooth plastic touch the ear, but, well, they didn't. You'll get used to it, but it's just an unnecessary design choice.Connection is quick with verbal feedback in the buds. Battery life is as expected, and runs easily the 6 or so hours; the case can give another 12-13. It takes longer than an Airpod Pro to recharge; it's worth charging over a longer break than just the few minutes other products can charge in. The case has a USB-C plug, but the included cable is tiny; throw a normal length one in your cart when you buy this. The case has no wireless charging ability, oh well. The case is larger than expected, a little heavier than an Airpods Pro case, and due to it's rectangular shape and width, a bit pocket un-friendly. The top does have a hinge-helper which holds the top open, something more cases should try.Sennheiser has an app for iOS and Android, and it really is necessary. It allows a firmware update to 2.13.0 that substantially improved connection speed. You can customize almost all the tap patterns; I added "play pause" to the right ear instead of just on the left. It also lets you store different EQ profiles (just 3 bands, so a bit gross, but better than nothing; there's also a "touch and slide" interface but it's really just a layer on the 3 band). The profiles are stored in the bud, and can be changed live via the app, even if you are listening to another source (so, using the phone to adjust the eq while listening to the computer). The app lets you control the connections as well; like most BT devices, you can't connect to more than 1 source hot at a time (aka no multipoint), and switching is still manual (Apple's Airpods ecosystem is more automatic, and Bose has done a nice job of having 2 sources mounted at once and having easy swapping between them).These are not sport buds: they don't quite stay in all that well (in my ears) when moving and have 0 water/sweat protection beyond the usual (a bit will probably be fine, but during a heavy workout, these re not fully protected from salty sweat.)So, other than odd choices in where to put the power connectors, the large size of the main block, the sensitivity of the touch panel, and oddities of the eartips size, the sound quality is amazing, far better than I expected from a Bluetooth connection, esp. for the price. Master and Dynamic has a similar pair that drop in price to around $100, and Yamaha has a nice pair around this price with similar specs, but after trying them all, I'm willing to put up with the odd design choices for that clean Sennheiser sound.