[point3six]

 
After a relative amount of research I have narrowed down my search to these cans.
 
*HD25-1-II, Denon D1100, Shure SRH840, Audio Technica ATH-M50, Ultrasone HFI-580*
 
What I'm looking for
- Over ear
- Portability
- Durability
- Isolation
- Powerful driver
- No supplemental amplifiers
 
I primarily listen to hip hop, although I listen to all genres including jazz and classical. I'm looking for a pair of headphones under $200 that can be brought on a bus, plane, or sidewalk and be enjoyed thoroughly. I want something that can handle being put in a backpack and lugged around, while also providing quality sound that overpowers outside sound. I will be solely using an iPhone/iPod and computer jack to power whatever headphones I end up getting. Other suggestions are more than welcome as this initial finding is somewhat preliminary.

 

[JRoMan]

I can't speak to the Denon or Ultrasone, but I have had the SRH840, which I chose over the M50 because I preferred the midrange presentation. After a year of taking back and forth to work, I sold my 840 and basically replaced it with two headphones: HD25-1 II for transporting back and forth to work, and HD580 for home use. The HD25 are light, indestructable, provide great isolation, can be driven without an amp, and have punchy bass. They really fit all your criteria except they are on-ear not over ear. Sound wise, I think the HD25 has better midrange than M50, though I never A/B them directly. You might also want to consider the V-Moda M80 or Crossfade LP2 based on your criteria, but I've never heard those. The Skullcandy Aviators are not bad based on transient listening in Best Buy/Apple Store, but I would question their durability.