„At a concert, the audience perceives this subconsciously; it contributes to the identification of the listening situation of a real concert.“
The prerequisite for my recordings of classical music is the fact that space and music serve together to fulfill a joint function. This means that any music that is performed inevitably belongs to an acoustically fitting space. When recording audio in 3D, with all the technological possibilities, I would like to place my listener on a chair in a space. It is from there that the audience perceives the musical performance. When recording, I try to interpret the acoustic situation, or ‘document’ it, and pass it on to the listener. This includes that a vocal soloist is higher up than the piano, or that the percussionist is higher than the strings and wind players in an orchestra. At a concert, the audience perceives this subconsciously; it contributes to the identification of the listening situation of a real concert. The positioning of the 9.1 speakers allows this sound situation to be reconstructed.
But not only that. Should the listener be seated more to the front, rather than in the middle, he or she hears more direct sound. If he or she chooses a place further to the back, closer to the speakers there, he or she hears more diffuse field parts. Which corresponds to the reality of a concert or a musical performance in a space. So the goal is to map the natural circumstances through the placement of the microphones. When doing 3D recordings, I place the microphones as follows: 8 microphones with omnidirectional pick-up patterns for the ambient sound and the usual main and spot microphones, as used for stereo recordings, whereas their types and pick-up patterns are dependent on the sound source. I place the microphones for the ambient sound in a matter that corresponds to the speaker placement for the rendition of 3D sound. This especially concerns the placement of the microphones in the vertical and horizontal levels. Which means that I set up tripods in the four corners of the room, depending on the position of the musicians. Mounted on each tripod are two microphone pairs on two levels. For the high level, the microphone height is a minimum of 4 meters. The vertical and horizontal distances between the microphones have to be determined by ear and depend on the size of the space and its furnishings. My experience shows, however, that it is best to work with a distance of at least 5 meters for the horizontal and 1 meter for the vertical level in order to achieve sound that is truly enveloping. The signals’ content and their correlations play a decisive role here: the distance (of microphones) from the source (both horizontal and vertical), the distance between front and back, the distance between left and right. It’s all about the timbre and the proportion between the direct and the diffuse sound field.
When it comes to depicting the sound source, I usually work with a Straus combination of omnidirectional and cardioid microphones as the main microphone. As I work without a center, while still wanting to guarantee the stability of the sources, I need more spot microphones than I would normally use for stereo recordings. For 3D recordings, however, I deliberately use these so that I can achieve the stability, timbre and contour of the instruments in postproduction. I mix the spots carefully into the front sound field.
