There are good reasons for people's criticisms of X/Y recording, particularly with cardioids. The main defect is a lack of spaciousness although that can be mitigated if two principles are followed. (1) is to use single-diaphragm cardioids (such as your Sennheiser 80x0s) rather than dual-diaphragm cardioids (e.g. nearly all large-diaphragm condensers), while (2) is to set a sufficient angle between the main axes of the microphones.
The reasons: For (1) it's essential to realize that a cardioid pattern just isn't sharply directional. In effect it's a 50/50 mix of an omni with a figure-8. If you place two cardioids at the same location, even if you set them facing in opposite directions (back-to-back), half the sound energy that they each pick up will be identical in intensity and time between the two channels, i.e. the mono component of this type of recording is at least 50%.
If you're into visualizing equivalences of this kind: A coincident pair of cardioids = a single omni mike coincident with a pair of figure-8s, where the left cardioid output = the signal from the left figure-8 plus the signal from the omni, while the right cardioid output = the signal from the right figure-8 plus the signal from that same omni.
But as bad as that situation is to start with, it's valid only for ideal cardioids. And among condenser microphones, only small, single-diaphragm cardioids can possibly maintain a cardioid pattern across their entire frequency range. The pattern inevitably gets a little narrower at the very top, because even what we call "small" microphones are "large" compared to sound waves in the top octave--but with larger microphones that narrowing begins farther down in the frequency range, so the distinction still matters. Meanwhile, dual-diaphragm cardioids--including nearly every large-diaphragm cardioid ever made by anyone--lose directivity at low frequencies, which means that a coincident pair of them will have an even greater overlap (signal correlation) between channels, just in the frequency region where the difference information is most responsible for providing a sense of spaciousness.
So that's why it's so important to use small, single-diaphragm cardioids, if you're going to use a coincident (X/Y) setup with cardioids of any kind.
For (2): In two-microphone stereo recording you don't "aim" individual microphones at sound sources; instead, you decide the width of sound field that you want to reproduce between your loudspeakers, and you set up your microphone pair so that its stereophonic recording angle fits the width of that field. You do that even if that means that your microphones "point" beyond the speakers or other sound sources. That's counterintuitive for a lot of people, but it's what works.
Now, I first learned how to record in stereo in the early 1970s, and back then the prevalent advice was to take two cardioid microphones and aim them head to head with a 90° angle between them. That was supposed to give good localization of sound sources--and in that respect yes, it did give acceptable results. But for one thing, the microphones actually blocked each other's pickup of high frequency direct sound; "head-to-head" microphone setups are hardly ever recommended any more for that reason.
But the main thing is, a mere 90° angle between two cardioids is like the situation I described earlier except that instead of a 50% overlap in what the two microphones pick up, the overlap becomes 75%. That's ridiculous; if the direct sound is coming from the front, then with a setup like that, the direct sound will be reproduced almost entirely in mono.
I really urge people if they're going to use X/Y miking with cardioids to start with, say, 120° between the main axes of the microphones--and depending on the room and the setup, an even wider angle might sound better.
--best regards
Topic: First recording with MKH8040 (Read 6922 times)