I ended up ordering a DX90 yesterday. I originally was interested in the AK100 but the impedance issue steered me to the X5 and DX90. I remember Jamato8 from his sage advice in the past and decide to take a chance on the Ibasso. I am pairing it with my JH13 and Roxanne iem. My sources up to this point has been recently Cowon S9, Sansa clip +, and BB Z10 using Neutron app. I'm a musician, bass player. I started out this adventure with Archos first mp3 player years ago.....scratch that, when I was about 7 years old and had what was called a "show n tell record player". It had a film strip that would advance as the record played. My parents had a restaurant, and we had a jukebox. I'm not sure how it worked, but after a certain period of time, the owners of the jukebox would replace the records and would give us the old records. Here I was a 7 year old with 100's of 45's for my enjoyment! I still remember the very first 45 I played, it was Paul Mccartney and Wings, side A was Jet and side B was mamunia. It might have been low fidelity, but that sparked an interest in music that lives on to this day.