I felt a stirring in the Force from being referred to earlier in this thread. Hi, people.
Yes, I've made live stereo recordings with two Schoeps CMC 58 (i.e. figure-8) microphones placed side by side, with an angle of somewhat less than 90 degrees between their main axes. I always left an inch or two of space between mikes when using this approach, since a figure-8 pattern can easily be spoiled if obstructions near the capsule prevent the diaphragm's exposure to the sound field from being symmetrical. Sonically, the results were fairly nice, considering the room--mostly I use this approach as a defense against rooms with low, flat ceilings. The nulls of the figure-8s reject sound reflected from the ceiling and floor, which makes the room seem a little less confining. As a bonus, figure-8s don't pick up diffuse room rumble, which cancels out on opposite sides of the diaphragm.
But (a) that's merely a practical adaptation to get listenable results in horrid little rooms where no music recording should ever be done at all, and (b) I believe the question was whether a Blumlein stereo recording can be made that way. The answer to that is no. Blumlein (a/k/a "Stereosonic") is a very specific technique; either your figure-8s are coincident in the horizontal plane with their main axes angled apart at 90 degrees (and the center line between the main axes is aimed at the center of what you're trying to record), or your setup isn't Blumlein.
Just as important: With Blumlein, the total horizontal arc occupied by the sound source(s) must be 90 degrees or less as "seen" by the microphone pair--a narrower pickup angle than with most other two-microphone arrangements. If you don't respect that limitation, you'll get what's technically known as "funny things" in the stereo image. Some of the same sound will be picked up in normal polarity through the front lobe of one microphone and in inverse polarity through the rear lobe of the other one at the same time.
Unfortunately, this means that for recordings of wide sound sources, Blumlein often can't be used effectively. Figure-8s are as sensitive behind as in front, so if you place them far enough away to "fit" a very wide sound source into the available 90 degrees of arc, you may well pick up too much hall sound. In some large concert halls that are relatively dry, this works out well. But in more conventional performance spaces such as typical "multi-purpose" auditoriums, Blumlein is practical only for recording chamber music, solo piano or other sound sources that don't occupy much physical stage width. The quality of the "natural" reverberation in a typical auditorium is quite unappealing musically, unfortunately.
When the technique can be used as intended, the Blumlein purists definitely have their point: This approach has the smoothest possible distribution of apparent sound sources within the stereo image of any possible two-microphone recording method, plus it's mono-compatible. My funny little side-by-side figure-8 approach has neither of those virtues. But as I said, it was just a way to get usable recordings rather than not get usable recordings.
--best regards
Topic: Schoeps "v" user... -> (Read 10035 times)