There are any number of technical features worth noting in the makeup of the IE800 but perhaps the most notable is that while the competition is mainly comprised of multiple balanced armature designs, the IE800 makes use of a single dynamic driver. As a company, Sennheiser has never been especially enthusiastic about armatures and as such has gone to the considerable effort of developing an all new dynamic driver for the IE800. This is called the SYS7 and has pretty much nothing in common with any other Sennheiser in ear driver. Typically, dynamic drivers have to give ground to armatures in terms of top end response but Sennheiser claims that the SYS7 has a frequency response of 5Hz to 46.5kHz. This is the widest bandwidth driver I think I have ever encountered in any product and means that - on paper at least - the IE800 has no performance deficit to competing armatures.



This driver is then supported by a complex mounting and housing that is subtly different from other in ear designs. The driver itself is mounted behind an absorbent assembly that is in turn behind a gauze and mounting system that is completely different to any other Sennheiser earphone. This is most noticeable in that the tip of the IE800 is not a tube onto which you place a rubber dome (more of which later) but a shallow raised ring that the bungs twist onto. Around the back, the housing terminates in a pair of vented ports that are made from stainless steel. The purpose of these vents is to tune the output from the SYS7 driver rather than augment them and they are unique to the IE800 - indeed I have never really seen such a system applied on any other earphone. The present of the vents does mean that unlike most IEM type earphones, the IE800 does leak some noise back to the outside world but not a huge amount.



This arrangement also means that the IE800 is in turn a significantly different shape to most of the competition. The single driver requires less space to house than multiple armatures and gives the IE800 a smaller teardrop profile when viewed from above. There are some engineering challenges to keeping such a relatively small enclosure inert when filled with a comparatively large driver and to this end, perhaps the most important deviation from any of the competition is that the housing is a single piece of ceramic. This has the double benefit of being impressively inert and additionally having different resonant properties to the driver it houses. It is also extremely tough. The housing can only be made as a single piece that means that the driver and supporting equipment is pushed back into the open end of the housing (the rear ports go in from the back and the cable presumably is pushed though from the bottom and connected up to finish). As this is decidedly specialised, Sennheiser made the undoubtedly wise decision to have the enclosures made by a third party supplier.



The result is unconventional in both technology and application but in one other key way is more ‘normal’ than many rivals. The IE800 is dependent on conventional silicone earbuds to make the seal with the ear canal. At this price point, many rivals are moving towards custom mouldings but the bespoke mounts of the IE800 mean that this is not practical. Sennheiser supplies a wide variety of sizes with each IE800 including oval buds that are designed to more accurately match the shape of an ear canal. This is a trade-off that means that the IE800 might not achieve the perfect fit of a custom mould but it is comfortable and convenient - you can buy a pair and be up and running straight away.

