Sennheiser IE 900 Review

Sometimes a popular new product will come out and I just miss it completely. So many new IEMs, headphones, and DAPs come out during the year that there are bound to be some releases I miss out on. One of those releases was the Sennheiser IE 900, their latest high-end IEM that I have been eagerly anticipating listening to for quite some time. I was so happy when they finally arrived at my desk, as I’ve been an admirer of Sennheiser for a while and know they can always be trusted to produce something I can enjoy. Let’s see if these $1,499 IEMs can reach their rigorous standard for sound quality.

Sennheiser Items

What You Get

  • IE 900 in-ear headphones
  • Balanced para-aramid reinforced cable with 2.5mm connector
  • Unbalanced para-aramid reinforced cable with 3.5mm connector
  • Balanced para-aramid reinforced cable with 4.4mm connector
  • 3 pairs of silicone ear adapters (S, M, L)
  • 3 pairs of foam ear adapters (S, M, L)
  • Premium carry case with metal serial no. plate
  • Cable clip, Cleaning tool & Cleaning cloth
  • Presentation box with signed customer certificate & User manuals

Senheiser single

Look and Feel

The IE 900 takes its body style from the IE 300, and with the IE 600 on the way, it seems like this is the design they are going to continue with for this series in the future. What is special about the IE 900 is its sleek anodized aluminum shell in a fashionable silver finish. It is an appearance that infers the earphone’s high-end nature while also suggesting a durable quality. These are still some of the smallest premium IEMs on the market, which works for their non-intrusive fit. I’ve gotten used to more cumbersome housing styles over the years, but it is nice to have an IEM that fits so easily in a universal manner that is both secure and comfortable.

Sennheiser Cable


You’ll see Sennehsier’s TrueResponse transducer make a return here, along with its single 7mm dynamic driver. These drivers are combined with three Helmholtz resonators and a special “Vortex” nozzle that helps shape the output in a way to ensure an intended sound profile.

  • Frequency response: 5 Hz – 48,000 Hz
  • THD: 0.05% (1 kHz, 94 dB)
  • Impedance: 16 ohms

Sennheiser pair


I trust Sennheiser to give me an exceptional soundstage for its flagship IEM, and the IE 900 delivers on every front. Their seminal HD 800s headphones are lauded for their incredibly wide stage, and that is what the IE 900 feels like in IEM form. Of course, the IE 900 doesn’t come close to comparing to the lush imaging of that headphone, but these IEMs appear like they are to IEMs what the HD 800s are to open-back headphones. That is no small feat, as the IE 900 brings out its spatial elements in a way that only a brand like Sennheiser can achieve.

From left to right, up and down, backward and forward, the IE 900 layers its sound spectrum with incredible separation and accuracy. Instruments and effects are weaved into the stereo field with an abundance of size and showcase dimensional properties naturally. You get an immersive bubble of sound that never feels like it extends too far outward, but sustains a headspace that is just on the rim of feeling like the music is coming from inside your head.

Low End 

I wasn’t expecting as big of a helping of strong, meaty bass as I got from the IE 900, and I was highly delighted by that. Its depth is pretty immaculate, operating its wealth of details in an expanding space that always makes every facet of its tone easily discernable. This is thanks to an abundant but clean sub-bass presence that gives every element of the sound signature that extra weight to its timbre. It is balanced with an equally impactful mid-bass that feels tight but never pulls its punches.


In the midrange, the IE 900 doesn’t try to match the intensity of its low-end, but still resonates with an even and detailed timbre that gives instruments and vocals their time of day. It’s a wonderfully natural tuning that still feels lively, and it establishes a sense of room that highlights each element individually. Even tracks that are very textural feel like they have an origin that makes their performances sound remarkably transparent when it comes to the mix. Vocals are always the main showcase of the midrange’s fidelity, and the IE 900 does them justice. Both male and female vocals appear realistic and almost like they are in a different space than the rest of the mix altogether. This gives them a floatier appearance in the sound signature, giving the performance not only uncompromised resolution but also height.


With the richness the IE 900 expresses in its lows and mids, it needs a stable and fulfilling high-end to cap off its sound signature, and it delivers that in a gratifying fashion. Its greatest characteristic is its ability to show restraint while moderately accentuating some of its frequency bands in order to feature just enough texture so as to not sound too flat or clinical. The most effective treble-focused instruments are granted a more potent grip on the timbre, showcasing detail while still going down smooth to those who might be more sensitive to this range of frequency.


My long anticipation to hear the Sennheiser IE 900 was worth it because these are some of the best IEMs out there right now. Every aspect of its sound signature meets its standard for detail and clarity, and it also goes above and beyond entertaining you with more colorful characteristics as well. Its price may be steep, but obtaining the IE 900 as an endgame for your collection is something exciting to work toward. With the IE 900 I feel like Sennheiser finally has their ace IEM that others can strive to compete with.

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The Sennheiser IE 900 is available at Audio46.

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Alex S. is a sound designer and voice-over artist who has worked in film, commercials, and podcasts. He loves horror movies and emo music.