As I stepped forward, this weekend we made our Spanish forum meeting and finally I could compare my TH600 to TH900.
First of all I have to tell you that I am not an audiophile expert, and am guided by my personal tastes. I was doing several times A / B with several colleagues, I have a Violectric remind V90 and is perfect for this, because it has two jacks for connecting 2 headphones simultaneously. Not only me, but more people found it difficult to find differences first. In my humble appreciation, differences I could find were the most powerful bass in TH900, but something more than in TH600 subgraves. The voices more advanced in the 900, and treble more accurate in 900, along with a little more transparency.
TH900 are obviously better, that I will not deny, but really the differences are very small and unjustified price difference between the two. I totally agree with colleagues who have said that a 600 is 90% of 900. True, the aesthetic appearance is also in the top 900, but again, still not justified the price difference.
Finally, I also wanted to mention that if you like and are used to the sound of Fostex is very difficult to find other headphones that impact you . At the meeting were better than just hit the market, Audeze LCD4 , HIFIMAN HE1000 , STAX 009 , and the best of the best made by peers. The full range of Audeze . HD800 several different rewired . Not to mention the best of the best also in amplifiers and there was nothing that made me say WOW . The ones I liked were the Audeze LCD XC closed . I found them very good, very good bass , delicious mids and a trebles, softer than Fostex, but the return to business as before, the price difference with the Fostex is abysmal . And by the way, the weight is unsufrible for over half an hour.