I have been using a pair of AD700 for the past year and a half, and am very happy with how it sounds: deep and wide soundstage, great clarity, controlled bass, great highs etc. Now I'm looking to get an upgrade, and all the research I've done so far narrows it down to the choices below:
Sennheiser HD600 (Probably best choice since it's more forgiving on the amp department, and it's well-known that recording engineers use it for making classical music recordings?)
AKG K702 (extremely popular among classical lovers but I don't have an amp that will do it justice and probably won't get one any time soon)
Beyerdynamic DT880 32/250/600 (I heard its sound signature is very different from the AD700s and the treble might be harsh?)
Denon D2000 (not open air, but generally regarded as a fantastic all-rounder that's also easy to amp)
Which one would give suit my needs the most? I listen to mostly orchestral music, solo piano music and some chamber music (string quartets) too. Sometimes even jazz trios. Cost wise, the Denons are the cheapest at $1800HKD, then the Senns at $2350HKD, the 702s being the most expensive at around $3300HKD. I use a Creative X-Fi USB HD DAC/Amp connected to my computer, where my FLAC library is stored. Will I hear significant improvements with whichever choice I ultimately decide to go with? I won't be upgrading to a desktop amp any time soon since I'm a starving college student and have little to spend on an audio setup, besides the headphones themselves.
Thanks a lot!