PerformanceThe Logitech UE 900s is clearly aimed to be used with smartphones or other portable devices. You even get two cables with the bundle; one with a neat in-line controller and microphone and a normal one.
One of my main complaints with the older high-end universals from UE was their fit, but that has changed dramatically. UE's old and abnormally long earphone-body has been replaced with a much more compact and stubby design. Logitech UE has gone a long way towards improving the fit by opting for a heavily sculpted design that should make it easier to align the nozzle of the in-ear with your ear canals. Of course, no two ears are completely alike, and you can never achieve a perfect universal fit that suits everyone, but the UE 900s are definitely on level with the fit achieved by Westone 4R in-ears, which is nice. The tip selection is great, but there is a gremlin in the design, comfort-wise. Logitech UE opted for cables with a memory wire! Such a silly nuisance to everyone with glasses, or oddly shaped ears, is a part of these high-end in-ears. The implementation is more elegant than on most custom in-ears, but it is still a poor idea! It only makes sense for stage musicians that route the cable along their back and twist it up to ensure an extremely tight fit. These cables are, apart from the memory wire, extremely well made and handle microphonics very well.
Besides the odd cabling choice, the fit works quite well. An optimal fit was achieved after a few tests with differently sized tips and insertion methods. You have to insert these in-ears in the same way as a set of custom in-ears to get the best out of them; at least with my ears.
Once the fit is there, you are in for quite a treat. The sound quality is definitely a far cry away from the Triple.fi 10s, which were the first triple armature driver in-ears on the market. The treble is not piercing, the upper midrange is not sibilant, and the bass is taught and extends well. There is a medium amount of sparkle and a slight rounded bass boost that helps accentuate the lows and the highs just enough to give them a fun-type sound. The midrange is by no means drowned out by the bass and the coloration of the midrange is very low, although it is a couple of degrees warmer than that of the Westone 4Rsand UE IERMs.
Bass extension-wise, these cannot match the Westone 4Rs, given it also has a more powerful bass. That is not to say that the UE 900s are bass light – far from it. They have enough bass to do pretty much any recording justice, but it is not as linear and extended as that of the 4Rs. The midrange presentation of the UE 900s is more spacious than the 4Rs, but at the cost of some realism, and the midrange seems a little further away than on the 4Rs. The treble is definitely more sparkly on the UE 900s, which makes them very entertaining to listen to.
Noise attenuation-wise, the UE 900s do a little worse than the 4Rs, but not horribly so.