Hello! I'm asking for help to choose the right headphone gear. Nowadays I've got Asus Xonar D1 and Sennheiser HD 558. Now I'm not satisfied with the sound it produces 'cause I can hear some clicky noise in highs (I don't even know how to describe properly what it's missing). I guess I just need more quality of sound. I ordered an amp already but I don't it's gonna improve a lot the current situation (Bravo Audio Ocean Mini).
I kinda want AKG 612 Pro however the price is overwhelming in my country for it. I also like Audio Technica ATH-AD900X, Beyerdynamic DT 990 pro 250 ohm or 600 ohm?! (the amp that I ordered, will it drive the 600 ohm beyers?). I listen to music only at home, so I figured that I need open back headphones. I don't have any music preferences: I love electro (Calvin Harris), pop, different club music, Beatles... I'm not into rock and rap music a lot however I love Coldplay.
I'd like to know what you think about the amp I ordered, did I make a mistake by ordering one? And what about my sound card, maybe it's too weak to drive my current HD 558 and other headphones as well? I really hope you can help me.