Kudos on the great review! I've actually been eyeing these for a little while now. I was most curious about the bass capabilities for being an open can. Not a basshead, but I do enjoy a fair amount for EDM. These just might be for me

Thanks. I'm ignoring this for awhile because I don't want to get interested in any more headphones!
Non removable pads on a headphone this expensive is a total fail. I would never buy a headphone unless I could remove it's pads.
I hope Philips actually listens to feedback and changes this.

Great review!  Well written and concise.  Kudos.

Nice review, the Philips models are better and better.. Wake up AKG!!!

I have had these since its launch. For large heads like mine, I've bent the metal headband to be more cone-shaped (Tyll mentioned that in Innerfidelity), as well as cut the elastic that threads through the lower cloth headband. I've also found that the ear pads can be pulled off and there's no real need to glue them back. They are held with 5 plastic studs that can just snap on and off. Then you can experiment with different ear pads - amongst those I've tried are Beyer velours, LCD, Mad Dogs angled pads, AKG K550. These pads may not look as elegant but the operative word is "experiment". Comments and pictures have been posted on the impressions thread many times in the past.

Great looking photos and well done review. Should be a great reference to potential purchasers.

Hello again! I just pulled the trigger on one, and your review was in part what made me decide to go with these cans.

Hnnngh. This review is not helping me save money...

The links to Amazon are for the L1, not the X1. The X1 is closer to $300, not $185.
 
I keep seeing people refer to sub-bass as 60-70 Hz. I think sub-bass is 40 Hz and below. 60-70 Hz is lower bass.

This makes me want the X1's even more. my wallet is itching. 

dpump : "I keep seeing people refer to sub-bass as 60-70 Hz. I think sub-bass is 40 Hz and below. 60-70 Hz is lower bass."
 
Right on, the lower end of the low-bass is 40 Hz. Below around 40 Hz the tones are breaking up, they lose their continuity [to human hearing].  40 down to 20 Hz is sub-bass.

And hear (jk) I thought all headphones were supposed to be "fun". Fun, fun, fun, fun, and fun.

This needs to stop being on the front page of Head Fi. It's headphone porn like no other.

@pragu LOL!!

It's disappointing to read that the pads are not changeable, not sure how that could have been overlooked on the design. Pads never last forever, with the fact you can't change them it basically adds a shelf life to these headphones and almost makes them impossible to justify spending money on. Too bad, because other then that they look like great headphones. The sound signature sounds very appealing and the design looks really nice to me.

A really thorough review!

me likes, thanks man!

Excellent review. Thank you so much for elaborating on the ear cup space. I owned both the K702 Annies and Q701s, and the drivers on the Annies DID touch my left ear and cause some irritation, but not the case with the Q701s. The angled drivers make all the difference. Something I wish the Senn HD650s had since they make my ears hot from the driver covers touching them. I also agree with you on the DT990 Pro. While the mid bass and lower bass are fun, the upper bass is a little too lean and makes the bass rather removed sounding from the mid range, and tends to sound somewhat droning and cold. Of course a tube amp DOES help some. An upper bass to midrange transition is crucial to a groovy and musical headphone, something the AKG K240 does extremely well, if it were not for that painful sibilance spike. 

I use an Inakustic Star 1.5M cable ( measured at 0.7 Ohm resistance) and the sound becomes much more neutral, sounding like a slightly warm DT880, which is perfect for me.