A lot of people get their priorities wrong on head-fi due to lack of experience.I didn't express myself clearly (Not that I ever do.), but what I mean to say is. If you find differently priced headphones to be comparable, like I did with 2C and 400i, maybe it is time to stop spending money on headphones, but instead spend the money on bringing your gear together? Like I did with the RME ADI 2 DAC, now the 2C easily beat 400i. It's subjective regardless. It's just that a lot of people on headfi, seem to spend obscene amounts of money on side grading. I did as well, because I could not find my sound signature. But 2C is as close as I will be. Which is why I was confused when I pulled my 400i out and it didn't seem that far off, which questioned why I bothered to upgrade to begin with. In any case I had some time to think about it and now that I am done side grading I'm looking at the higher end, but just having a look. First I will sort my cable situation, get decent cables in, for headphones and whatever else I need. ADI 2 DAC + HA-1 as a headphone amp isn't a bad combination, but I would like to get Phonitor XE to step in for that, maybe not this year, but eventually... Then I can look at the high end of headphones with my priories straight.
Your priorities must be (1) headphones, (2) amp, (3) DAC, (4) source files, (5) cables.
1, Headphones make the biggest difference. Find your preferred sound presentation and spend the most you can afford in that category. (Dark/bright, musical/analytical etc.)
2, Amps can bring out the best of your headphones but pairing matters a lot. Do your research. And spend the most you can after you have found your perfect headphones.
3, The importance of DACs is underestimated in this hobby. DACs can improve technicalities way beyond your imagination. Get the best DAC you can.
4, Poor mp3 will sound poor, regardless your fancy gear. FLAC is the minimum and must have quality.
5, Cables bring the subtlest difference. If you have got your chain sorted, play with it. However keep in mind, cables are only the cherry on the cake.