Sonic Defender
Headphoneus Supremus
Looks like Audio-Technica has some new lines coming out and they look legit
http://www.pocket-lint.com/news/139156-ditching-the-dac-audio-technica-dsr9bt-bluetooth-headphones-go-all-digital-with-pure-digital-drive-tech
Now we just need more phones with aptx HD.
Looks promising, I like the larger driver idea, but they are going to be expensive it seems. I also don't think we can hear any distortion from DACs so the whole direct digital I think is marketing more than an audiophile need. We can measure DAC distortion, but it is inaudible based on everything I have read and experienced. Ultimately the most important thing all things being relatively equal is the voicing of the headphone and how well cabinet resonance is handled. I would pay extra for really good cabinet design more so than I would pay for something like Direct Digital.