Hi...I presently have the EarSonics SM64 and I love the sound of these. As you can tell from my sig I have had W4R & UM3X as well. I listen to rock, classic rock, blues & jazz primarily. I have a Fiio X3 as my main music source and listen to mostly high bitrate mp3's and FLAC. I would like a sound signature close to what I have or have had that is easier to drive(more efficient) than the SM64. Any Help? Budget no more than 500.00 Suggestions?