Design of a Coincident Microphone Array for 5.1-Channel Audio Recording Using the Mid-Side Recording Technique

In this paper, a 5.1-channel audio recording method is proposed by applying the mid-side (MS) stereo recording technique to a coincident microphone array. The coincident microphone array consists of a backward-facing cardioid microphone and the MS microphone array which is composed of a pair of forward-facing cardioid and sideways-facing figure-eight microphones. These 3 microphones produce two bi-directional signals and one uni-directional signal through additive and subtractive procedures. Using these signals, the rotated uni-directional signals are produced and synthesized at each angle according to the 5.1-channel speaker array. The performance of the proposed 5.1channel audio recording method is evaluated using a directional response test and a localization test. It is shown from the tests that the proposed recording method provides a beam pattern well at each direction on the basis of the 5.1channel speaker configuration and has localization performance within ±8.2 degrees.