Hi katumonu, actually, my first chamber concert that I am preparing for is this week. I have also read some articles (and books), and I have concluded that I should use the ORTF configuration with cardioid microphones. So, I will position the stand so that the microphones point to the left and right edges of the ensemble, and above the ensemble by 50-70 centimeters. I may also try A-B configuration (spaced pair of microphones) with omnidirectional mics, now that I own a pair on the same stand. Then I will be able to compare both recordings. It would be my first try with A-B, and others here (TommyBoy) have warned that A-B with omnis will work very well only if the acoustical properties of the hall are very good. If not, ORTF will be much more reliable. So we shall see what I capture! I have two more chamber concerts to record before I get back to the full orchestra.
Back to Katumonu; I’ve done two chamber concerts this week; one was a bass recital that had several numbers featuring solo bass, and a couple of numbers featuring bass with piano backing, and two with another bassist. The second chamber concert was a performance of several wind configurations, from solo flute to wind quintet. In both cases, I used the ORTF configuration for my main pair of mics, and I had a second set of mics going into a separate recorder, and based on my setup, the second set of mics was closer to DIN configuration. (The second set of mics were next to, and just above the first mics, but slightly outside the first pair). The mics were about 2 feet above the players’ heads, and maybe six feet back.
This mic configuration worked very well for me. I would say I was very satisfied with the overall stereo effect. I will use ORTF again for chamber recordings.