Audio

This wikipedia article describes the fundamentals of microphone usage and techniques. A related article describes the history and variety of microphones, as well as when to use which type of microphone.

The Zoom H6 kits used in Digital Art, Video and Photo classes contain three types of microphones:

  • X-Y Stereo
    • [Source article]Here there are two directional microphones at the same place, and typically placed at 90° or more to each other.[8] A stereo effect is achieved through differences in sound pressure level between two microphones. Due to the lack of differences in time-of-arrival and phase ambiguities, the sonic characteristic of X-Y recordings is generally less “spacey” and has less depth compared to recordings employing an AB setup.

      Blumlein Stereo

      When the microphones are bidirectional and placed facing +-45° with respect to the sound source, the X-Y-setup is called a Blumlein Pair. The sonic image produced by this configuration is considered by many authorities to create a realistic, almost holographic soundstage.

  • MS Stereo
    • [Source Article] This coincident technique employs a bidirectional microphone (with a Figure of 8 polar pattern) facing sideways and a cardioid (generally a variety of cardioid, although Alan Blumlein described the usage of an omnidirectional transducer in his original patent) facing the sound source. The capsules are stacked vertically and brought together as closely as possible, to minimize comb filtering caused by differences in arrival time.

       

      The left and right channels are produced through a simple matrix: Left = Mid + Side, Right = Mid − Side (“minus” means you add the side signal with the polarity reversed). This configuration produces a completely mono-compatible signal and, if the Mid and Side signals are recorded (rather than the matrixed Left and Right), the stereo width (and with that, the perceived distance of the sound source) can be manipulated after the recording has taken place.

  • Shotgun
    • [Source article] Shotgun microphones are the most highly directional. Their directional pattern has a very narrow lobe in the forward direction and rejects sound from other directions. They have small lobes of sensitivity to the left, right, and rear but are significantly less sensitive to the side and rear than other directional microphones. This results from placing the element at the back end of a tube with slots cut along the side; wave cancellation eliminates much of the off-axis sound. Due to the narrowness of their sensitivity area, shotgun microphones are commonly used on television and film sets, in stadiums, and for field recording of wildlife.

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