Well here goes after 3 hours compare and contrast of my two beauties! (I've had TH900 for about 18 months). All testing done on same equipment to allow direct comparison, my Colorfly C4, which has plenty of power for these two at half volume and has great synergy.
Physically:
Aesthetics
X00- Beautiful cups, nicely finished, well finished pads and jack end, etc.
8/10
900- Equally beautiful cups, excellently finished superior lacquer, with slightly nicer jack end.
9/10
Overall- Its slight win for TH900 for slightly better fit and finish, but only slightly. Overall beauty in eye of beholder....I love them both.
Feel
X00- Much lighter than 900...probably due to reduced magnet size (think these are defo based on TH600). Same headband as 900 but lighter weight makes them more comfortable with no issues from extended listening. Pads are same quality but more padded and less room for ears, but still adequate to be over ear. The downside is less options for placement and slightly warmer to wear over a longer time.
8/10
900- Noticeably heavier (nowhere near Audeze weight) than X00, but headband is still comfortable. Pads are great...spacious, airy and comfortable.
8/10
Overall- Dead heat, with the 900 having more comfortable pads and X00 more comfortable weight.
Sound (using a range of hi res music from Michael Jackson to HDTracks samples, Elliot Smith, Shawn Colvin, Daft Punk, etc)
X00- Bass is generous, warm, impactful, slightly soft and creates a very similar wonderful atmosphere (which so many phones struggle with). The mids are definitely more present on more tracks, not that the TH900 can't express great mids too on some tracks....the X00 just does it more often. The treble is probably the biggest difference to the 900, with much more taming. I've never thought the 900 too sibilant or harsh on anything other than bad recordings.....now i'm not so sure and I really like being able to turn some music up without an increase n harshness. Very impressive, but not without a flip side compared to TH900.
8/10
900- Bass is world beating joy. Treble is detailed, airy and tread a fine line on some tracks, of being a little on the edgy side. Mids are good but take a polite step back to let mr.bass and mrs.treble do their merry dance. Resolution is up there with the best other flagships have to offer. The bass and treble extend more than the X00, which makes nearly every track sound impressive, with enough quality overall to keep the mids pulled along behind, to make even the hardest nosed Headfier toe tap along. Not every type of music needs this though...and it is here that the X00 warrants its place proudly alongside the 900.
9/10
Overall- I'll try to keep this brief and more instinctive from my initial listen.....The X00 is like listening in a smaller room with sound deadening on the walls....very intimate, clear, a very collective sound in balance. Very suited to acoustic music, better for vocal representation in the overall presentation than TH900, such as Elliot Smith, Shawn Colvin, which is exactly what I was looking for in filling a weaker part of the TH900 armoury. However, what is lost from losing some of the extension to the bass and treble is the feeling of being in a big hall, with church like acoustics when listening to the TH900, with its great sense of airiness and separation between a songs elements (an open headphone like presentation). I guess this is the euphonic reference people make...but also the mark of a flagship can which together with its slightly superior resolution, which will make you smile often. I'll give to the nod to the TH900 still, but I will say...especially to all of you non TH900 owners is....you lucky lucky people. You've now got the Fostex house sound, with much of its atmospheric joie de vive and enthusiasm for enjoying the music in a slightly more charismatic way than may have been originally intended....which is no bad thing in my eyes. Bravo Fostex, Massdrop and all of you who took the blind plunge
THX00- 8/10
TH900- 9/10
