SpiderNhan
Headphoneus Supremus
Yeah, at this moment, not thinking of such a high price. 50-75 USD at the max, and that too only if there is a significant difference. (was hoping from China, there might a non-mainstream, but really good one which punches much above its weight, like the IEMs )
I'm thinking, I'll spend $200, if I upgrade my headphones to HD 650, which definitely require a good amplifiers. But at $200, wouldn't DFR be a better option?
DFR is bit hindered in Android implementation. Only USB Audio Player Pro offers the full playback capability. Using the DFR with apps like Google Play Music, Spotify, YouTube etc. the volume control is limited and may not be sufficient depending on your headphones/IEMs.