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  • Introduction

  • Design

  • Features & Performance

  • Conclusion



Heavily and brilliantly engineered, but not without some durability concerns

From an aesthetic standpoint, these are some of the prettiest in-ears out there. The unique design implies a rather large amount of time spent in development. Design features largely reflect the basic in-ear headphone archetype: there are two ceramic buds that house Sennheiser's prized drivers, silicone sleeves, and Y-shaped cable. Also present on the oxygen-free cable (OFC) is a break-away jack, to prevent the most violent tugs from breaking your in-ears, but the real meat of the story here is what goes on inside.

Not only was Sennheiser able to cram in a single 7mm extra wide-band transducer into a tiny in-ear monitor package, but by avoiding the previously standard balanced-armature design, the extra noise and distortion that comes in even the highest-end in-ears by splitting the reproduction of frequencies over three drivers is all but eliminated. I was able to catch up with Sennheiser's Senior Acoustic Engineer Axel Grell (famed for designing the HD 800s and HD 700s), and he was able to fill in many of the innovations that make these in-ears special. The short of it is: they thought of damn near everything.

According to Mr. Grell, in-ear headphones have many pitfalls inherent in their design, and not many people are aware of the engineering challenges that come with creating this type of headphone. For example: due to the shape and length of your ear canal, creating a seal on both ends will exacerbate a resonance with frequencies in the 7-8kHz range (depending on your individual anatomy); this can make your music sound like it's suffering from low-frequency "loss," due to the presence of higher frequency noise of a greater power sum masking the bass notes. The solution? Use an absorber to remove some of the energy generated by these resonances so your music won't be impacted by this difference in force.

If that doesn't sate a nerdy appetite for brilliant solutions to difficult physics problems, there's more where that came from. Grell continued to explain that by adding dual vents behind each tiny magnet in the IE 800s, he is able to direct air wherever he pleases, thereby avoiding the addition of extra distortion to your music. With countless features like these, it's clear that these headphones were created in the pursuit of innovation, not just to fill a market niche.

If there is anything unfortunate to be said about the IE 800s, it's that their driver design makes them highly susceptible to irreparable damage. While it may be obvious to some, those teeny tiny wires coming out of in-ears are very fragile—the only thing holding them in is often an equally tiny solder point, which can crack very easily with even minor tugs over time. In-ears really just aren't that durable by design, so owning the IE 800s could be a bit terrifying if you don't have a huge pile of cash to burn.

When confronted with this issue, Mr. Grell patiently explained that there really wasn't a way to keep the IE 800s as small as they are and have removable ear buds. In addition, the most common breakage point in their labs was actually near the 3.5mm connector on the opposite end of the cable, so they added a male 2.5mm audio plug at the convergence of each channel's cable to allow the use of different and replaceable female-to-male cables, for in the event that breakages do occur. To extend the life of the non-replaceable cables, Sennheiser has woven kevlar (shown in green on the cables) around the wire insulation to prevent snapping. Not entirely ideal, but it's a substantial step in the right direction for such an expensive version of a very fragile model of headphones.

Features & Performance

From a performance standpoint, these in-ears certainly have the guts to do well.

Unsurprisingly, since launch, the Sennheiser IE 800s have won a few accolades based on their design, and it's no mystery as to why: the German headphone manufacturer has crammed a lot of headphone into an extremely tiny package, resulting in an ultra-premium set of in-ear listeners. By the spec sheet, we'd guess these things will work without an amp, and maybe even do well with a mobile device, too, which is thoroughly unexpected for a set of headphones this expensive.

Sennheiser intended for this to happen: according to them, this is the set of headphones they want for you to buy if you're looking for "audiophile [...] on the go" listening. With a 24ohm impedance and a sensitivity of 125dB, these are headphones that can operate on a lower current than most, and that gives them a decided advantage for mobile use.

But why on earth would you? Most smartphones (outside of the outdated Nexus S) use somewhat crappy digital-to-analog converter (DAC) chips, meaning the source of your music is not likely to give your headphones the "audiophile level" signal so prized by enthusiasts. While the IE 800s themselves are legit, most of the supporting cast of possible mobile audio equipment isn't quite where it needs to be to keep up.

Despite their billing as headphones that can take audiophile-level listening on the go, it's probably more wise (in terms of getting a decent return on your investment) if you baby these as much as possible. Realistically speaking, this probably means leaving them at home to use with your own equipment, even though they seemed to attenuate a good bit of the noise coming from the ~76dB (at that moment) show floor. Yes, I have a dB meter; don't judge me.

Unfortunately, we are not able to elaborate on the exact performance points of these headphones—we'll need our lab to do that—but we are confident in reporting that these have clearly been labored over to a possibly unprecedented degree, and that many of the innovations that appear on these in-ears may crop up elsewhere. Once we get these into our labs, we'll be able to inundate you with all the saucy details on how these premium features measure up.


Clearly, much time, effort, and expense has been poured into these headphones. That said, it's impossible for us to give you a full picture as to how well or how poorly these things will do, nestled snugly in your ears, but the power requirements make it seem like these are intended for mobile use. Despite this, your supporting cast of equipment is not likely to make the best use of the hardware unless you continue to use a source with a solid DAC chip. It may end up being terribly impractical, but there's a certain appeal to that sort of thing: who doesn't want a super-powerful car or ultra-expensive toy?

Tied for first place with price, the biggest knock against the IE 800s is their durability. Despite Sennheiser's press release, which hails them as "durable", most tiny cables with appropriately small solder points are anything but. In-ears break. A lot. Normally this sort of thing isn't a huge problem if you're looking at a pair of cheapo in-ears at the drugstore, but these are terrifyingly expensive. Sennheiser did make a serious effort to add in a bunch of measures to prevent breakage, but it's unclear as to whether or not it's enough: especially when the weak point in the headphones is so glaring.

Given their pedigree, and given the success of the previous HD 800 and HD 700 headphones, we're betting that these pricey in-ears are going to make a big splash in the audiophile community. And that's fine: there's nothing wrong with wanting to make an investment in your headphones (something I am very, very guilty of). The trouble is that these headphones have rather notable issues that challenge the long-term sensibility of sinking that much money into them. However, as pointed out by Mr. Grell, these headphones represent a triumph of innovation, and that could mean very big things for headphones of the future.

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.

See all of Chris Thomas's reviews

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