Andre, I'm using my ears because in my experience measurements do not do an adequate job capturing sound differences. But in any event, M-Audio or RMAA are not really the last word in test equipment so my doubts remain how flat the iPhone really is. If you go to Head-Fi, a large number of people do not find the sound quality to be very good at all. I find this opinion valid based on my own experimenting with various sources from iPods to hirez files>dacs>amps.
1/11/12 at 8:29pm