Did a mic comparison experiment yesterday relating to the 2 cheapies vs 1 better mic question. Put up a 603 pair and a single Schoeps mk41 at the same position on a nylon string guitar doing fingerstyle solos. Set up the 603 pair in XY first, then also in closely spaced AB to use them on and off axis. Distances were 1 ft, 2 ft, and 4 ft out from a spot between bridge and soundhole, which is the best spot for this particular guitar. Good sounding room 35'x15' with 16' peaked ceiling. Used Mackie pre's on all, then also tried the 603 pair through my 2 channels of Great River to be more than fair to them.
Imperfections of the experiment: The quality difference between the 603 and the mk41 is more extreme than the mic's mentioned in the thread, though the idea is the same. The mk41 is a supercardioid so has a much tighter pattern than the 603, so to be more scientific I probably should have set it up a little further away than the 603 pair. The 603s have a high end bump, and the mk41 is flat, but the room's high freq qualities are very good and it was a mellow instrument, so there wasn't anything bad there for the 603s to pick up. Finally, I'm not impartial as I already had A/B'd them when I first got the Schoeps a couple of years ago. But I wanted to reassess.
Listening back: Close up, the mk41 sounded a lot better than the 603 pair, and the quality difference increased the further away I got. Focused, firm low end, very sweet highs from the mk41. Using a little Waves linear EQ on the files to test how they responded to changes, the 603 pair didn't take EQ very well. The mk41 files responded well to EQ no matter what the changes were. Everything stayed clear and sweet. The stereo soundstage qualities of the 603 pair at the 4 ft distance were nice but not nearly good enough to compensate for the sound quality difference. And if I added a subtle reverb to the mk41 with ReverbX or SIR, it widened the single mic nicely. Moreso if I duplicated the mono file and processed each side differently with EQ or offset it a little in time.
I've often heard that good mono beats bad stereo, and it was interesting to try the experiment.
Tim