**above** the ensemble, which produces an odd perspective, unless you happen to know that that is where the mics are placed.
Wood floors and microphone height above floor are key in recording. The floor will produce comb filtering as the sound is reflective from it and cancels with teh primary sound - it creates a pleasing spacious sound. Depending on the instruments there are a variety of rule of thumb positions for mics - choral works are often recorded with overhead mics.
BTW - this happens with your speakers in your room too particularly in the low midbass where soudns radiate in all directions => you get quarter wave cancellations off the wall behind the speakers.
They key to this effect is a large flat reflective surface which is positioned symmetrically with repect to the microphone or listener. Some sudios have special plates just for this purpose although often recordings are now made in a an acoustically dead booth and th esoudn of a platye is added by using a reverb (the advantage is you can dial in any reverb you want)
For example side walls do not produce this effect in a listening room - only the rear wall behind the speaker and listener which is symmetric with the bass and midbass frequencies. It is the same for a microphone - if you want to maximize the effect then the mic needs to above the source of sound so that the sound is in between the microphone and the reflective floor.
I recommend Bob Katz book (Mastering) for people who want to read up on this. I am sure Ralph knows more than I do about all this - but I thought many readers may be unaware of this - although as an audiophile I think it is only natural that one should want to understand this stuff (nearly half of what we ever hear is reflected sound)