I really wonder how Oppo HA1 sounds. So far, I have used portable digital audio players only. How would you guys compare Oppo HA1's sound to sound of AK240, Calyx M, AK120, HM901 and Fiio X5? Is it so much better?? if so, how would you describe it? I'm a classical, soundtrack, rock and electronic music listener. Would you recommend this unit to me? I'd like to hear you guys' opinion. I personally never owned a DAC like Oppo HA-1 before. P.S. I use Shure's SRH1840 headphone with Moon Audio's Silver Dragon V3 cable.