[KillJoyPuppets]

I've always loved high quality audio, so I'm seeking to buy a good pair of closed over ear headphones. Right now, I'm rocking some $15 in-ears, which are good, but I'm looking to step up.
 
I've done research on all four of these headphones. I started with the ATH-50s and was encouraged by all of the positive reviews. But there were several complaints regarding proper balance in regards to mid-level frequencies. Links and suggestions directed me to Ultrasone HFI 780, which are my primary point of interest right now. But I have also heard many good things about the others referenced in the title. 
 
One of my concerns is that I'm not seeking to use an amplifier at the moment. I just want to be able to have a good pair of standalone headphones. Although, I will be happy to hear any suggestions with amplifiers. 
 
I have also looked at Beyerdynamic DT-770 Pros. However, the lower impedance models (32 ohms) are considerably more expensive. The 80 and 250 ohm models are less expensive, but I was concerned on being forced to use an amp to at least achieve a reasonable quality. So if any suggestions can be made, or if any explanations are offered, they may become a consideration as well.
 
I have a very broad musical palate.
Several genres and artists just to help gauge suggestions:
Pink Floyd
Metal - Metallica, Iron Maiden
Electronic - such as house and dubstep
Jazz - John Pizzarelli, or Big Band
Indie - Elliott Smith, The Antlers
 
Thanks!

 

[ToInfinity]

I'm switching between both as I type. 

 
There is a very noticeable difference between these two headphones. When listening to any of the genres you mentioned, the M50's sound muffled in comparison to the 780's. The bass in the M50's is ridiculous..sometimes in a good way though. It does seem to bleed through the rest of the music, becoming the most prominent element of most songs, if there is a decent presence of bass with the song itself. I did mention this could be a good thing, you can really feel the bass, especially with dubstep/house. On the other hand, the 780's sound a lot tighter and cleaner..not as much bass or the good rumble feeling, but again...tight and clean. Now that I've established that the bass is the main focus of the M50's, it has some other drawback besides making music sound muffled. It also make the mids sound a bit recessed, and they are I guess, but it may be the case that the mids aren't lacking - necessarily - just that the bass is too much. There is a huge lack of balance and neutrality, obviously. Bass heads would be pleased though. Now, talking about the 780's....
 
As I said, the 780's are very tight and clean when it comes to bass...although they are lacking (IMO of course) in sub-bass. I prefer the sub-bass to be excellent rather than mid-bass....for me, the sub-bass is what can really take you to that place where it's only you and the music and your soul. Mid-bass is for more fun and upbeat and to get you moving. Sub-bass will make you close your eyes and take off to another world. The mids-highs are noticeably sharper. Female vocals sound better, guitar strums and symbols have a more defined impact. 
 
Conclusion: M50's    7/10
 
Too much mid-bass that bleeds through to the rest of the frequencies, mostly effecting the mids, making them sound a bit recessed. Good rumble that you can feel to a decent extent. They don't dig down REAL deep, but deep enough. They are still a decent pair of headphones though. More laid back. 
 
Conclusion: 780's     8/10 
 
Not much sub-bass to speak of, although the mid bass hits hard enough to be effective. Much more balanced than the M50's. Clean, tight, and more defined. Has more of an attack and slightly better decay (very important with layered techno).