Good Evening folks. A while back I decided to upgrade my phones. I am currently sitting on a pair of AKG K518 LE, which sound OK. Though are EXTREMELY uncomfortable, I have to shift them constantly. Also the sound leaves a little something to be desired. Anyway, after many hours of researching I have managed to decide - two of them. However choosing one over the other seems impossible. The headphones in question are Beyerdynamics DT770 Pro 80Ohm and the Sennheiser HD598. From what I have gathered, and I would gladly be corrected, the differences between these two seem to be. DT770 - Very bass heavy, very comfortable, lacking in mids, seems to require a bit more to run. Closed. HD598 - Neutral sounding, "weak" bass, good all around headphones. Open. With that said, I have some questions about open headphones, since I have only owned closed ones before. Just how much do they leak? If I crank the volume up, will people sleeping behind a door fairly close hear the music? I also understand I would be able to hear stuff around me. Say I have a desktop computer next to me with 7-8 fans going on high RPM just a few meters away. Will this interfere will my music? I certainly understand each of the headphones is better for a certain type of music. Though I really listen to EVERYTHING, from classical to hiphop to drum and bass. As well as playing video games/watching movies with said headphones. I also like bass but I do not want it at too big cost of sound quality. I think it needs to be said that I do not currently own any DAC/AMP/Soundcard. I use the onboard souncard on my Asus P8Z68-V Pro. Originally I wasn't planning on buying anything, but something cheap like a Fiio E10 I could consider if it would improve things noticeably. Basically I would just love someone to help me decide on which headphone to chose, of course other suggestions are always welcome. Though they need to be decent sounding and comfortable to even be considered. I hope my message comes across in this somewhat incoherent rambling and that someone shed some light on the problem.