Clearly you know what you are talking about on this subject and would just like to say That form my point of view the dx50 is a great sounding dap and that's only because I believe I have not had the the experience of testing many more of these products. I am fairly new to the audio world and strive for great sound as long as my budget allows Me so . Would love to hear the ak120 or the hifi man hm901 but my funds will not stretch that Far as yet .do not fully understand the terminology you use it's all double Dutch to me But I know good sound when I hear it. The ibasso is a good player but I do know there is better out there and can't wait to Experience it for myself . That's why you great people are helping me on my journey to great sound that I can live With and be totally content . Obviously I do not know the complete meaning of neutral sound or the other things you Mentioned like air between instruments , roll off and all the other terminology that goes With it . Willing to learn so I can give my proper opinion in the future .