Also consider adding the Digizoid ZO2 to your chain. I have one and I really like it. I use it with the SE215s.

You can get official Apple parts from Apple (store.apple.com). That cable will run you $20.  You can get 3rd-party cables from monoprice.com. Looks like you could get one for about $6.  You can also get this cable from Monster Cables for between $20 and $30.  You could also buy a small pile...

The ATH-WS70s wear pretty well.    http://www.youtube.com/watch?v=brt1VhuCHoQ skip to 8:10

Consider the Shure SE215. You have to wear them over-ear, mind.

Looking at your list, you might also consider the amperior, momentum on-ear, or one of the many Audio-Technica portables.

Haha, yeah, amp no question.

Richardson0, 990s no question.

Will you need an integrated mic for Skype?

I own both the 770s and 990s. I actually bought them for the same reason you're looking at them. I listen to a lot of tech-house, R&B, and electronic pop. I like bass. I leave the 770s at work because they provide a good amount of isolation which I need to stay sane. The 990s stay at home...

I second this, but note that I have a ZO2 in my chain. I do wish they were a tad brighter.

Or the DIY forums.

If an amp blows your headphones while you are wearing them, you will have bigger problems to worry about. The EF-5 and Lyr are fine choices. Just keep an eye on the volume knob.

The Tasktar HD 2000 is listed as 32 ohms. Even though you shouldn't really need an amp, you could see some improvement. I picked up a Fiio E07 a while back and was very happy with it, especially with the bass boost. I did find that the battery in my iPod Nano drained quite a bit faster when...

From what I've seen, any DAC for your iPod is going to cost about $600. It's a lot of money for something that's not going to make a big difference for you.

What you report sounds like under-powered headphones. What are you plugging them into?