Thanks  @Quinto!

Awesome review peter.
I am looking for something that would complement my T50RP, this might be it.

@getclikinagas  thanks! Interesting, I actually thought of making a comparsion with the T50RP but since both my pair are modded I decided against it. From memory the X2's got better extesion in both ends while the mids are full and nice on both. I think that if you like the T50RP there's a fair chance that you'll enjoy the X2's as well.

Ah thanks. The mids are quite special on the T50RPs. I haven't modded mine yet. Just soaking in the stock sig before I do.
 
You've mentioned that  sounds great off multiple sources. I have a GO450. I take it this should sufficient?
I do hope I get to audition them before I purchase. Philips' weirdly limited release doesn't do me any favors :/

@getclikinagas Yeah, I've got the GO720 myself and they pair very well. The 450 should sound very similar and have more than enough power for them.
 
If you can hear them first that's certainly the best but Philips product doesn't seem to be that widely available everywhere.
 
You're in for a treat modding those T50RP's

Have been listening to my friend's X2 today with my iBasso DX100 (firmware 1.2.7). Sounds ridiculously good with it, almost as if it's been voiced specifically with it. It's such a great combo that i purchased one earlier today and will get it by next weekend.

I own the X1 and I'm curious how does it compare to it? It is worth $100 more? 

Bass is tighter and better controlled on the X2 compared to the X1. Otherwise the only difference between them is the new all black color scheme and replaceable pads for the X2. IMO not worth getting the X2 if you have the X1.

Thanks Nicolo, that's good to know. I doubt i'd be the type that can hear the difference between then regardless. Will wait for the second hand costs to drop first. 

Congrats Peter for front page. Great review for a great headphone! My favorite full sized as well

@Baycode Thank you very much! Yes they're truly great

Awesome review. These are on my radar now. Can anyone offer a quick comparison between these and the HD600s—the only full-sized cans I currently own?
 
Incidentally, "Unshakeable" is one of my preferred tracks to use when analyzing headphones and demoing my car stereo for buddies; and "Them Bones" is one of my all-time favorite AiC tracks. 

Id like to extend on what nicolo just stated a little more. The bass is much tighter but also looses a bit of extension compared to the x1. For me it seemed as if the mids got a tiny bit of a boost and the treble a little bit more extended. I think the x2 is worth the upgrade just because of the replaceable pads, the refined tuning is extra. Having a $200-$300 headphone and no replaceable pads is a no-no in the audiophile world IMHO. But it didnt keep me away from the x1's when they first came out. But when the x2's came out its a no brainer for me. So im going to jump on getting a pair. My buddy has had his pair for a while and i plan on getting a pair myself. I held off because i had an opportunity to purchase a pair of lcd2s.

Very nice review!
I own the X1s and I love them. But on some recordings there could be a little less/tighter bass and a little more sparkle in the treble. Almost every comparison between X1s and X2s I read suggests that these things are fixed with the X2. Hmmm.
The replacable pads alone do not justify the extra 100 bucks in my opinion as Philips offers no replacements. So this is a little bit pointless. There are also reports from users who successfully got off the pads from their X1s and put them back in place. There are the same pins as the X2s have them. So it seems as Philips wanted to make the pads replacable on the X1s but the construction was not good enough so they used glue in addition.

@Bibo Thaks! 
Yeah, It's my impression as well that the bass on the X2's are more controlled (especially mid-bass). I demoed the X1 many times when they were new and alwayd found the bass to boomy for my liking so I never purchased them. When I demoed the X2's before my purchase I didn't feel that. Take this with a grain of salt though since I've never compared the two at the same time.
 
I also agree with you on the pads, better think of them as non-replaceble until Philips proves us wrong

I too own these headphones and LOVED them right out of the box.
 
This is an Excellent review, really good and thoughtful.
 
I own a pair of Grado PS500's (I prefer the X2's), a pair of Hifiman HE-300's (I prefer the X2's) and a pit of Hifiman HE-400i's which I like only a tad more.
 
For me these headphones are what I wanted the Senn 650's to be, at less cost. Great headphones and review.
 
Well worth the money. I run them directly with an iPod Classic and Lossless Files plugged right into the Cayin C5 and THAT is a lovely match although truth be told they sound good with every amp I have.

Very nice review.  I'm also glad to hear that these sound good with different amps as I am still woking out what amp I want to go with.

@muchtooloud Thanks for the  kind words! I'm glad you're enjoying yours as well
 
@pedalcolorado  Thank you!

Very nice review!  How well do you think these would perform with more complex music like symphonic metal and orchestra?

Great review. What is that cable you're using? I'm trying to find some shorter replacement as well.