Hello everyone. Recently I decided to invest in the NuForce Icon HDP, or E9 and E7, and the new handset. I am interested in HD650, HD600 or, HD598. I see the AKG K701 is also quite popular in conjunction with this kit. I want to know which of these handsets will play best with a combo that their opportunities will be presented at 100%. Currently testing the E9 and E7 from the HD555 I miss the bass, he never listened to any other DACu and probably have the characteristics of play. Looking for something better to POP, Hip-Hop, Techno, House, Rock. I would like HD650, but I'm afraid that will not play properly in all types of music. The second type is the AKG 701, but they never heard of, but people say they have little need proper bass and an amplifier. Sorry for the language, I hope that someone will understand me.