· Stereo microphone setup techniques and their quirks.

· What we (the group I am in for a recording project) will record as demonstration of said stereo miking techniques.

· How we intend to go about capturing the performance(s).

This configuration is a physical analog of a mixing technique which goes by the same name. Our lecturer, Phil Thompson, explained last Tuesday (16/11/2021) Mid-Side can refer to mastering a track by splitting it into an additional mono track with added compression. Compression of dynamics affects stereo width, so by separating the stereo track into its own spaced pair (through a plugin or hard-panning) we are able to control how much we blend a comrpessed mono and non-compressed (or even expanded) stereo tracks together.

In this case, the mics act as a hard-wire form of this method in capture, rather than mastering, and the mic acting as mono captures what is ahead using a Cardiod/Unidirectional polar pattern, while the mic acting as stereo in Bidirectional/Figure-Of-Eight (F-8 for brevity onwards in this text) can be split into 2 signals that become hard-panned away from each other. This allows us to have an emulation of stereo via having actual stereo width, which we can blend with the mid channel to invoke the Mid-Side dynamic effect. Some microphones have 2 inputs, one for each side. This can give a true stereo output, though we will likely not use a microphone like that.

We would want the 2 mics to be as close to each other as possible to avoid issues regarding phase, and they should ideally be positioned as a relative perpendicular pair.

This configuration is a stereo pair using F-8 polar pattern, which (if panned down the middle) can almost imitate an Omnidirectional microphone. However, when they are panned we can have 2 sides picking up a lot of room sound. Mic R captures the right +ve but also left -ve, and vice versa. This allows for a hardware form of a stereo-expanded Omnidirectional pickup pattern. But the main difference between an Omni mic and a Blumlein pair in the same position in a room, is that it picks up a different stereo image depending on the shape and materials present in the room as well as having an inverted directionality of the reflection sound relative to the sound source.

An advantage this has is that, like the Mid-Side config, trying to get the ideal position of the mics being as close as possible also eliminates issues with phase.

While the first name here is an obvious description, the second name refers to [L’]Office de Radiodiffusion-Television Francaise, a French Radio-TeleVision (believe it or not), which employed this technique. This method allows for a replication of human hearing due to the 2 mics being placed on the same point and just facing different directions, the example here being 110°.

This is similar to the previous technique, but instead of the mics being on a point angled away from each other, they are instead in line and spaced apart (and likely perpendicular). This can be very suitable to capture a wide source, like a line of musicians whether it is an orchestra, choir, or any situation where there’s a wide source.

This technique was one we thought we couldn’t do due to size limitations (though there is more to say about that later). The Decca Tree is most similar, out of all previously mentioned techniques, to the Mid-Side. However instead of a Cardiod & F-8 set up perpendicularly, there are 3 Cardiod-pickups with one in the center, and the others typically 1+ metre(s) from the center, with the central mic being approximately 80cm higher than the lateral mics (which are typically 2.5 metres higher than the sound source). This is very geared towards recording choirs and orchestras. This has an advantage of stereo/mono compatibility and was developed by Roy Wallace, Arthur Haddy, and Kenneth Ernest Wilkinson. This configuration is associated with Decca Records.

We have decided to record the Student Choir at our University. This choice was made for the sake of originality, but also an opportunity to record a source that is physically wide.

We have been given the blessing by the Head of Musical Theatre to do so on one of their Christmas performance rehearsals, so long as we don’t get in the way.

Their rehearsals are at 16:30 at the lecture hall.

This hall is fairly large, and has stepped seating where long desks can reflect sound, and the seating can absorb sound. A more detailed analysis on this can be made at a later date.

We intend (which doesn’t mean will necessarily will be able) to use a field recorder, a pair of AKG C-414’s, an additional mic for attempting an approximation of the Decca Tree, and all the other equipment necessary to record (such as cables, mic stands, tape measure).

We must also make sure not to record one voice more than others, and try to attain a balanced reproduction of what we are capturing (though, of course that, in large part, depends on the choir).