Do not get this headset unless you are considering amplifying it. It sounds bad without an amp.
 
My Experience: These cans sound nice when amplified/ bad when not amped. Good highs, okay lows, overall pretty good sound. They are closed and will block out the outside world. I have worn these for up to 6 hours at a time and still found them comfortable. 
 
The mic can be raised and lowered but does not automatically shut off when raised, and requires the button on the clip to be switched which can be a pain in the ass at times. 
 
My mic died on me after 2 years of use, so I opened it up and soldered a new mic onto it in the most ghetto way possible than duct taped the mess back together. 
 
Cord tangles very easily and will get destroyed.
 
They can also take quite a beating as they have flown off of my desk many a time and still performed perfectly despite my abuse towards them.
 
Conclusion: They served me well and I really enjoyed them. My one major grip with them is the lack of a removable cable. 
 
 

I have only had these headphones for a little over a month at the time of me writing this review. I choose to write the review now because I feel confident in my ability to properly asses these headphones from an objective point of view with minimal bias. This review was written at work over the course of a shift, it is by no means well layed out. 
 
First off....These headphones are understandably flat and dull when used without an amp, anyone expecting auditory greatness (Over the Ear) from a 3.5mm jack running off of your phone is insane. 
 
What I listened to on my HD650s: Classical, Rap, Rock, Classic Rock, Metal, Death Metal, Melodic Death Metal, Symphonic Death Metal, Alt Rock, Dubstep, Trance, Jazz, Techno, Pop, Progressive Rock, Progressive Metal. Television shows, Movies, PC games, Skype conversations. 
 
Quality of source material: Primarily 16-bit 44KHz ALAC, Vinyl, 24-bit 96KHz FLAC
 
What powered my HD650s: Tested on 2 amps at home in addition to my portable amp solution Fiio e17
 
Use: 6-8 Hours a day for a little over a month at home in chair/bed, walking, and even in my car.
 
Experience: Easily the best headphones I have ever owned. The bass response is superb and will lull your ears into nirvana. The highs are crisp and distinct but never feel like they are stabbing your ear canal. I decided to test MP3s with the HD650 and was astonished at how 320Kbps tracks were sounding through these cans. No where near perfect, but damned impressive for the source material. I listened to music the most sitting in my lazy boy chair at my computer or laying in bed. I have actually fallen asleep listening to these headphones, they are really comfortable. 
 
Conclusion: This review was kind of sloppy, but I can easily recommend these cans to anyone looking for a delicious audio experience. AMP MAKES ALL THE DIFFERENCE