At first I was disappointed limitless, because if those things do not fit exactly, there are, as some write here, virtually no bass. If you make it, however, completely seal the earphones, meets a sudden a handsome powerful bass. In this case, there is virtually no limit. Either you have 100% or 0% bass. So you can hear very clearly when these things are properly seated.
The sound is then a total of more balanced, more bass but it should not be. I personally would like to see even a small bit more treble.
Those who believe, however, that a Koss Porta Pro is the desired optimum, probably will not be happy. (I personally do not like the Koss because it kills anything for my taste with his bass.)
At the same time you have a totally different perception of ambient noise, since you mainly just listened to what is transmitted by the body through the bone to the ear. The remaining ambient noise are greatly attenuated. That's the goal of in-ears! For audiobook fans sure optimal. The ears will thank you when you do not hear in concert volume to drown out the surrounding noise. In road traffic, but still be careful. A bicycle bell is taken may no longer was.
Sony provides with 3 different sized rubber plug to match the in-ears on the ears size. You have to experiment a bit to find out the best combination for yourself, for a good seal and on the other the sitting pleasant. Not only the right size of the rubber stopper is crucial, but also the exact position in the ear. Whether that every riff is undecided.
Bottom line: if they fit correctly, you get a good sound for the price and can hear pretty quiet thanks to the strong shield.