Sennheiser IE 900
For The Audio Purists
Unlike phones, flagship IEMs don’t come around often. Sennheiser’s last flagship-class IEM, the IE 800 S, was released in 2017. So you can imagine the excitement the new IE 900 caused when it was announced earlier this year in May. The move is a concerted effort by Sennheiser to refresh its IEM lineup which started in January this year with the IE 300.
The IE 900 and IE 300 share the same design which is no bad thing. The IE 300 was supremely
comfortable to wear and the IE 900 is no different. It fits snugly in my ears. And because it’s so small and light – a mere 4g – you’ll barely notice it.
While the IE 300 is made in China, the IE 900 is made in Germany. It’s an important point of distinction because only Sennheiser’s most important and premium products are made in their German factories.
On the materials side of things, while the IE 300 makes do with a hard plastic shell, the IE 900 features a milled aluminium housing. Each IE 900 shell starts off as a block of aluminium which is then precision-milled to create its unique shape. This step is particularly crucial because within the aluminium shells are three Helmholtz resonator chambers that were designed to minimise unwanted frequency peaks.
The IE 900 uses MMCX connectors. The connectors are specially designed so that they sit within a recessed socket so that there’s strain relief. This might cause compatibility problems with aftermarket cables, so pay attention to fit if you intend to use your custom cables with the IE 900. Bundled with the earphones are three cables with 3.5mm, 2.5mm, and 4.4mm plugs for use with a wide range of balanced and unbalanced devices.
These cables are made of para-aramid which Sennheiser says can withstand “many thousands of bend cycles”. They certainly feel durable, but are quite stiff. Coupled with the fact that they are coated in a TPU material, makes them feel like rubber hoses.
Unlike other companies that differentiate their earphones by using drastically different drivers, Sennheiser prefers using variations of the same driver across its lineup. Therefore, inside the IE 900 is a
7mm TrueResponse dynamic driver that’s closely related to the driver inside the IE 300.
While the driver may be similar, the tuning treatment most definitely isn’t. In the case of the IE 900, the three precisionmilled Helmholtz resonators for example, is something the IE 300 lacks. Greater attention has also been paid to managing airflow and backpressure, evident by more prominent vents.
Some readers might also wonder why Sennheiser opted for a single dynamic driver setup. The reason, explains Sennheiser, is that while multidriver configurations might achieve better frequency response, they do so by sacrificing timbre, coherence, and phase performance.
Tonally, the IE 900 sounds mostly even. Bass response is
tastefully elevated, and crucially it is tight and punchy. But it is the treble extension that really gets you because it’s so well extended and smooth. There’s no harshness or sibilance, just lots of air and sparkle. The problematic area for me is the mid to upper mids, there’s some unevenness there so vocals sound breathier and more hollow than they should.
Technically, the IE 900 is quite resolving and detailed, but perhaps not quite to the standard one might expect from a summit-fi IEM. I attribute this to the unevenness in the mids to upper mids. The breathier vocals can sound indistinct as a result and some instruments like pianos and guitars do not sound quite as incisive. Imaging is solid and the stage that it projects is slightly wider than average, which makes well-recorded live recordings a treat.
Against the much more affordable IE 300 ($449), it is clear that the IE 900 has a more balanced sound, with more resolving power, and is appreciably more detailed and clean.
Judged solely by the way it sounds, the IE 900 is competitive but not classleading. Where it really outshines its competition is with its superlative build and compact design. It feels bombproof. And because it is so small, it’s supremely comfortable to wear. This addresses a common issue with high-end multi-driver IEMs – many are too big and torturous to wear for any extended amount of time.
Ultimately, like most other German-made products, it’s practical and sensible – as sensible as $1,999 can be. I think the people who buy it will be very satisfied with their purchase.
RESPECTABLE AUDIO, BUILT TO VERY HIGH STANDARDS, AND IS MORE COMFORTABLE THAN MOST, IF NOT ALL, OF ITS RIVALS.