The mathematical transformation of the Mid-Side microphone array (M-S) to stereophonic left and right outputs results in an equivalent coincident microphone configuration (X/Y). The output pattern of the combined mid (M) and side (S) signals can be altered by manipulating the polar pattern of the mid (M) microphone and by adjusting the ratio between the M and side (S) microphones. This study investigated the technical and perceptual attributes of equivalent M-S and X/Y patterns in order to determine the consistency of the theoretical with the practical application. A simulated jazz sextet was recorded using a selection of M-S, and their equivalent X/Y, techniques. Each pair of recordings was measured to compare the timbral and spatial attributes of the equivalent configurations. Listening tests provided a perceptual metric of this theoretical equivalence. Comparisons and subjective ratings provided a more complete picture to determine whether the mathematical transformation was supported by perception. A significant preference for M-S techniques suggested the mathematical equivalence transformation model does not reliably predict an equivalent stereophonic perception of X/Y and M-S recording configurations.
Wesley A. Bulla
Entertainment and Music Business, Mike Curb College of
Master of Science in Audio Engineering (MSAE)
audio engineering; bidirectional; cardioid; coincident; microphone; mid-side; omnidirectional; psychoacoustics; stereophonic
Hauer, B. T. (2019). "Mid-Side to X/Y Equivalence: Turning Microphone Theory into Practice." Master of Science in Audio Engineering (MSAE) thesis, Belmont University, Nashville, TN. 5. https://repository.belmont.edu/msaetheses/5