My first goal was a recorder that would allow me to record some of my vinyl records and provide as close an experience to analog as digital can do. Secondly, I wanted the capability for live music recording. 1 bit recording seemed the right way to go and the reviews I read on the Korg MR-1 seemed to prove that until I actually got one.
After recording a record I listened to it on my all tube system and noticed a lack of good image and flatness in the medium to top end. This was true for PCM and DSD modes.
Being an electronics engineer I wanted to measure what my ears seemed to detect and downloaded a program for my PC to generate tones and tone sweeps. I ran this into the Korg MR-1 and watching the level VU meter on the Korg, I could clearly see that frequency response started dropping off sharply about about 400Hz reaching a floor in the 5-8KHz range, down a total of approximately 5-6db.
Clearly this was not spec (+-1db) so I called Korg and they told me that they had not seen such a thing and it needed to be fixed. Since it was out of warranty I returned it and got yet another one which again demonstrated about the same response curve.
I have tried doing the same test using my iMac and running the output into my Nakamichi Dragon to observe the VU response there. All seemed to coorelate.
So I wonder if anyone has actually tested the frequency response. I could easily imagine someone recording live music and listening later not realizing how much was really lost.