I do not have this headset for a long time, and do not feel the ability to describe its sound reproduction or the pleasure it gives me already but still want to deny such remarks: "This requires a headset {sic} amplification dedicated to make it work properly. " I plugged the Sennheiser HD600 headphone jack on my Onkyo small chain on the receiver dac E10 Fiio and my portable digital player (Cowon C2 *) and the music is, every time, just made audible, listenable and enjoyable. Even exciting. I rediscover albums I listen for years. One can not expect better.
* Note that the HD600 is large, it does not isolate all and your neighbors will hear it very loudly. As such, it would be inappropriate to use it in public.