Meet the Sennheiser CXC 700s (MSRP $229), a set of active noise-canceling in-ears that are probably best used on an airplane flight. While these headphones are not well-suited to use on a jog, the active noise cancellation unit employed by the Sennheiser CXC 700 offers better attenuation than most on-ear or over-ear headphones. Still, there are some durability issues that should give most people that are not frequent travelers some pause. While they're fairly comfortable for in-ear buds, the CXC 700s' in-line remote is clunky and annoying. At first glance, the Sennheiser CXC 700s present with some very standard options that are common for headphones that are geared towards the traveler. With the Sennheiser CXC 700s, you get a standard 3.93 ft cable, 1/4th inch adapter, an airplane adapter, and a standard 1/8th inch plug. As previously mentioned, there is an in-line remote that is more Sisyphean boulder than boon, but it is necessary for the amount of additional electronics added to the unit itself.
There is an in-line remote that is more Sisyphean boulder than boon.
With the added carrying case, your Sennheiser CXC 700s should be able to go comfortably wherever you do. Because in-ears by design are typically very light, the Sennheiser CXC 700s won’t weigh you down (assuming you’ve clipped your remote on something). If you don’t have a pocket to clip your remote on, however, you will find that your headphones will feel a lot heavier on your ear canals than they should be. Because the cables are usually the first thing to go (especially when they’re as thin as the ones on the CXC 700), be extremely careful about how you store these, and also how much pressure you put on the solder points of the remote. In the short term, several around the office reported that the initial fit of the Sennheiser CXC 700s was about as comfortable as in-ears tend to get. Overall, though, the fit depends on how well the included tips go into the ear canal. Because there are only 3 sizes, some may find that they can’t get an ideal fit, but at least it’s better than just having one size. Over time, the fit doesn’t really change, and the only thing that will change that is tugging from the massive remote, which we recommend you clip to your shirt. Barring any tugging on your in-ears, the fit shouldn’t change. Decent quality, though a little heavy on the bass and high mid-tones. The CXC 700s tend to favor bass frequencies over others—not by a ludicrous amount, but enough that you'll notice the added volume in most of what you're listening to. They also emphasize high mid-tones and lower treble (high) tones, so things like sibilance noises ('s' and 'sh') and cymbal splashes may be notably louder than what you're used to—it's potentially unpleasant, but nothing to worry about too much.
The CXC 700s have three separate modes of isolation for you to choose from.
As for distortion levels, these ear-buds have a small amount, though this should be inaudible to all of our readers, unless you are a Head and Torso Simulator robot. The channel preference for the Sennheiser CXC 700s is mostly even, save for two semi-audible shifts at the lowest and highest ranges. Most users will not hear it, so there's really nothing unwanted added to your music. Within the arena of isolation, the Sennheiser CXC 700s do attenuate noise fairly well, making outside noise appear only about 25% of its original volume to listeners (at worst), which is a substantial reduction. The CXC 700s have three separate modes of isolation for you to choose from, and one of them (the strongest) works in a slightly quirky way that we'll detail further on the science page. Overall, not bad, but the remote a surprisingly big drawback for these headphones. All in all, the Sennheiser CXC 700s perform much better than their price would indicate. A somewhat high price tag isn’t such a horrible thing, but the user experience is tough because of the remote. It’s big, heavy, causes durability concerns, and in some instances can even cause pain while listening if used improperly. All that aside, the distortion is notably low for an active canceler, and the frequency response is great for music listening. What we’re looking at here is a set of very solid headphones, geared to the frequent air traveler. Because airplane engines tend to output a lot of noise—noise that can damage your hearing on long trips—it’s a very good idea to attenuate some of that droning, so the active cancellation is a feature worth the money. Still, there are some (not many) better passive attenuators for less if you go that route. As far as consumer headphones go, the CXC 700s are a rare gem under $300 for active noise cancelers. It's true that they have their quirks, but so do all headphones, and these function very well overall. Just be sure that you can figure out how to take the load off the heavy remote somehow, and you'll be golden. The lion's share of what we dislike about the Sennheiser CXC 700s lies with its disproportionately sized in-line remote—though this isn't a performance feature. On the audio quality side of things, the CXC 700s are decent noise-cancelers, delivering an great frequency response, a low level of distortion, and mostly even tracking. The most interesting performance points here lie with the frequency response, and how these buds work to actively cancel noise. An interesting frequency response. For the most part, the Sennheiser CXC 700s manage to stay relatively within our ideal limits, but there are a few anomalies that are worth mentioning. For instance, the 0-350Hz range (the bassiest sounds, synths, and kick drum attack) is emphasized, as well as the 7-9kHz range (where you’d find most of your sibilants and cymbal sounds) will sound a lot louder than the rest of your music. Not ideal for those who prize a flat response, but many people like emphasis in these ranges, as this response looks a bit like an equal-loudness contour in most places. The CXC 700s have three different isolation modes. The Sennheiser CXC 700s are interesting in that they have three separate modes of active noise cancellation that you can choose from. Using the one that blocked out the most noise (in our labs), you can see something bizarre happen. For whatever reason, and against all logic, turning the active cancellation unit on actually makes the attenuation worse than the passive attenuation in some ways. We struggled to explain this phenomenon away, but the only conclusion we could come to is that because of the selected destructive interference pattern, additional noise must have been pumped into the ear canal by the headphones. Overall, though, the Sennheiser CXC 700s do attenuate noise fairly well, dropping total sound pressure levels (SPL) down by an average of just over 19dB.

Meet the tester

Chris Thomas

Chris Thomas

Staff Writer, Imaging


A seasoned writer and professional photographer, Chris reviews cameras, headphones, smartphones, laptops, and lenses. Educated in Political Science and Linguistics, Chris can often be found building a robot army, snowboarding, or getting ink.

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