Im currently using sennheiser pc360 headset as an open backed headphone for producing and listening to house style music. I believe it uses the same drivers as the 558. I actually really like the sound signature of these headphones, Neutral lows and nice highs. I ordered a pair of dt880s to test but the high end was to zingy and fatiguing for my taste. Would you guys say the X2 has a similar sound as the pc360 or would another sennheiser headphone such as the hd600, hd 598 be a better choice for an upgrade?
Also is it the x2/00 batch i shoudl be looking for or the x2/27? Does anyone know if the current batch on amazon UK is absent of these quality control issues i keep hearing about?
The X2 has a warm tilt, as in there is a gradual increase of bass linearly sloping towards the bass. Check out Tyll's measurements on Inner Fidelity for measurement graphs of each headphone you're interested in. I would recommend the hd600. you can get a secondhand one in the calssifieds for between 200-300, which is the same price you would basically be paying fro the X2s. the 598s might not be enough of an upgrade for you from the pc360 to justify the extra cash. If you want a monitoring headphone that is neutral and sounds fantastic to listen to music to at the same time i would recommend the R70x. It is not on your list, but among the headphones I own its one of my all time favorites.
That being said, you cant go wrong with the X2s. They are exceptional sounding, exceptionally built, and veeeeryyy comfortable for long periods of time.
For reference I listen to a lot of chillstep, house, and melodic dubstep