Move it, baby! Or: Mike it in stereo, dear recordist.

Compare many studio recordings with well recorded, minimalistically miked live performances and you will notice that the latter often contain more "space", and movement within that space, making them sound even more live. Why is that so?

- When music resonates in a space the intensity of the sound at any one spot changes over time.
- In real life most musicians move while they are playing.
- When musicians move, their instruments move with them, with the obvious exception of musicians performing on a fixed instrument or set: pianists, percussionists, organ players come to my mind.
- When an instrument moves in space it continuously projects (different frequencies) in different directions.
- This movement is as much part of the musical performance as the notes played, the texture of the sound, the dynamics and timing etc.

Set up a single microphone to mike a musician's instrument and it will record only varying degrees of sound pressure as the musician moves closer and farther, on and off axis. Most of the acoustic effects of any movement in space will be lost.

What to do?

- Recording in a good sounding acoustic environment.
- Position the ensemble so that you can capture a balanced sound stage with a main stereo microphone.
- Use (few) stereo pairs for spot miking.

Then the only thing left to do is for the musicans to move it :-)

Don't always go for 100%

I'm just now listening to a stack of so called audiophile CDs I borrowed from a friend and notice that on quite a few titles the entire width of the sound stage is used in a way that places direct sources full left or right. I don't think that is a good idea - in general.

The way I perceive it a sound stage that leaves some room left and right creates a more realistic space. All sound having a phantom location and being localized from the area circumscribed by the set of loudspeakers can never be as well defined as sound that originates from one of the speakers only.

- Use the appropriate configuration. XY at +- 90° and AB at about 50 cm cover an area of approximately 180°, ORTF 96° and Blumlein 76° (see an overview for more detail).

- When tracking, the main stereo setup should be placed so that (a little) more width than the original sound stage is covered.

- Coincident configurations allow you to safely(1) manipulate the width of the recorded stage in post.

- In many cases additionally tracking a flanking pair of parallel omnidirectional microphones can help restore the balance.

- Regarding the positioning of musicians it is important to place them linear with regards to the distance between one another rather than linear with regards to the angle as seen from the main microphone setup.

- When panning sources to create an artificial space, the difference in level or in sound pressure (16 to 20 dB) or the delay of one side relative to the other (1 to 2 msec), or a combination of both factors, should be chosen to not be "extreme".

This is my opinion, so YMMV. Let your ears be the final arbiter.

(1) You don't experience (as much) comb filtering due to phase differences in the signals being combined.