So your question is, "What headphones are good?" Oh boy. That's not going to go too well.
If you're looking to buy headphones and you're looking for a recommendation, it's easier to give us a list of parameters and let us give recommendations to accommodate your needs, instead of making a popularity contest thread and then slogging through the many myriad responses.
So, some questions for you:
-We've established your budget, $400 USD.
-Are you looking for open or closed headphones? Open back headphones have no noise isolation, leak sound, tend to sound airier and typically have a larger soundstage. Closed back headphones isolate sound and tend to have better bass quantity. Are you going to use your headphones in a noisy environment or a quiet one? Will there be other people around you while you are listening who would be bothered by ambient noise coming from your phones?
-Are you looking for something portable? For home listening? Or both?
-What is your source? Laptop, iPod, CD player? If you're using files as a source, mp3? FLAC/ALAC/lossless? If mp3, what bitrate?
-Something like AKG K701 cannot be adequately driven via a headphone jack on a laptop or iPod. If you were to try, it would likely sound muddy and anemic. This being the case, if you then intend to get something harder to drive, do you plan to invest on the appropriate amplification?
-What is your musical preference? Rock, rap, jazz, etc. Please be specific.
-Is there a certain sound signature you prefer? Do you like lots of bass? Lots of treble? etc.
-What headphones do you currently own? Is there anything in specific you've tried and liked?
-Do you have a place nearby where you can go to try different headphones out? Auditioning is the best way to decide which phones sound good to you.
The more information you provide, the easier this will be.
Welcome to Head-Fi.
Edit: Looks like Classakg beat me to it.
