Home Review Sennheiser IE 900 high-end in-ear

Review Sennheiser IE 900 high-end in-ear



  • Sounds very controlled
  • Beautifully made
  • Ultra neutral
  • Multiple cables


  • Prefer more earplugs
  • Critical placement in ear
  • Not ours

Price: € 1299

Build Quality
Sennheiser IE 900


When Sennheiser comes out with a new reference in-ear, we have to have a taste. Surely they are the reference in the market when it comes to personal audio. Just look at the HD600, HD800 and the HE-1 to name a few. These are all models where others are being compared to. In short: We are going to see how they do with the IE 900 in-ear. A set of in-ears that will set you back…. gulp… 1300 euros.

For those who missed it, Sennheiser has put its consumer head-fi arm on sale. Now that’s not very worrisome, as companies do tend to choose the path of focus. Sennheiser sees more in pro-audio and b2b products and solutions. EPOS is a part of Sennheiser. And it’s doing quite well, although I’m sure the many home-based jobs are debit to that succes. We digress.

Back to the IE 900. The Sennheiser IE 900 was not developed yesterday, of course. There has been a whole process preceding it. Sennheiser has developed a 7mm driver for the IE 900 that covers the entire bandwidth. That is a different approach from what many other manufacturers opt for; they go for multiple units to split the bandwidth. There is something to be said for both. If we look at the phase response in the measurements, we understand Sennheiser; it is dead tight. That’s almost impossible with multiple units.

Now it is also true that it is difficult to get a dead straight response with one unit. At least with a loudspeaker. There is always a compromise: either bass pressure, or open and neutral high frequencies. We’re curious to see how Sennheiser has made that balance. In any case, you can already see it in the measurements.


The Sennheiser IE 900 comes with six caps to ensure a good fit: a pair of foam-like caps and the familiar silicone caps. Now these come in 3 sizes: small, medium and large. Unfortunately we are a bit in between medium and large. With some pushing we get a good seal with the large caps, but for your editor that is less comfortable. Medum does not provide a good seal and is a bit loose. This is at the expense of the seal and the bass response.

The finish is excellent. It should be, considering the price. But still: it all looks very good. The materials – think aluminum casing – are high quality, the cable does not tangle and the storage case feels premium. Should you ever break the cable – which is very difficult, but eventually everything can break – then it can be replaced: the cable is connected to the familiar coaxial connector.

For those who may not be familiar with putting in in-ears like the IE-900: the cable goes ‘behind the ear’ and then the plugs go into the ear. The piece of cable that goes behind the ear is flexible and stiffer. The advantage of this method of insertion is that the cable no longer pulls on the ear plugs and there is also much less cable noise. The disadvantage is that it takes some getting used to to find the right angle. But well: that takes some practice. In the end it is really more comfortable. Let’s go and listen.

Type test
Single Test
Speaker class
Monitor - bookshelf
Speaker type
Speaker system
Bass reflex
Signal control