This is my first post on here so I hope it's a decent one. I purchased a pair of HD700's a couple of weeks ago and I let them burn in for 200 hours. I changed the cable over to the Moon Audio Black Dragon balanced cable. I have been using these headphones in a portable system with great results. I have the ALO RX MK-3+, the Cypher Labs Solo db, Moon Audio Silver Dragon line cable, and an iPod. I have been through so many headphones but I am really enjoying these headphones the most. I find these phones to be detailed without sounding bright, the bass goes down deep while remaining tight, the mids are very transparent, and the soundstage is wide. On this portable system I have used the Hifiman HE-400's, Sennheiser HD600's, Beyerdynamic T90's and even the HD800's which I really only use in the house on a Melos amp. The Hifiman HE400's are fun headphones which I like but they can sound dark and lack detail even with the velor pads. The T90's I did not like at all. I found them to be way too bright. I like the HD600's overall, there is not much to complain about with those except that they can sound diffuse. The HD800's have amazing detail and dynamics but they can sound a little thin to me. They don't quite have enough bass. Here is where the HD700's come in. The sound quality falls somewhere between the HD600's and the HD800's. They do everything better then the 600's without the brightness of the 800's. The 700's are fuller sounding then the 800's too. They are not as detailed as the 800's but detail is not everything. These HD700's make me want to get out to the track and walk. I walk for a couple of hours sometimes and I really enjoy it. In a way these headphones contribute to lowering my blood pressure!!
I am sort of new to the headphone universe but I have been into and own a high-end audio system using speakers. I have the Pass Labs 350.5 amp, Audio research Ref 3 pre-amp, Magnepan 3.7 speakers, 2 Velodyne DD+15 subwoofers, Meridian CD player and a VPI turntable. Audio has been my passion for 30 years and I have owned so many different high-end systems. I wanted to mention all my equipment because I wanted to show how much I am into audio.
I hope this post helps.