The Eigenmike Spherical Microphone Array for Recording 3D Spatial Audio
The Eigenmike® spherical microphone array for recording 3D spatial audio
With surround sound playback becoming standardized for broadcast, film and AR/VR applications, the demand for surround sound recording solutions is rising. The two main solutions to recording spatial audio are object-based recording that uses multiple discrete microphones to record each source or scene-based recording methods the utilize higher-order Ambisonics (HOA) microphone arrays. The strength of HOA microphone arrays is their flexibility in terms of the number of output beams, beampattern design, and beam-steering direction from a single device. All processing is done electronically without the need for physical movement of the array itself. HOA microphones also allow for post-processing enabling the conversion to different surround sound standards and post editing of the spatial reception of the microphone. Spherical microphone arrays are particularly well suited for surround recordings since the underlying geometric symmetry records the field with no dependence on orientation. Another advantage resulting from the spherical geometry is the ability to realize low computational complexity sound field decomposition and beamforming: a first stage that spatially decomposes the soundfield into spherical harmonics base beampatterns (Eigenbeams or HOA) that are then used as building blocks to a second stage that forms the final desired output beam patterns or rendering processing. This talk will discuss the Eigenmike® spherical microphone array and its suitability for use in recording higher-order Ambisonics for spatial audio capture.
Gary W. Elko started his professional career at AT&T Bell Labs in 1984 after completing his BSEE degree at Cornell and MS and Ph.D. degrees at the Pennsylvania State University. Dr. Elko was a Research Supervisor of the Electroacoustics and Signal Processing Group in the Acoustics Research Department at Bell Labs working on acoustic signal processing related to full duplex hands-free speech communication. In 2002 he cofounded mh acoustics with other Bell Labs colleagues. mh acoustics works with customers on the development and implementation of acoustic signal processing algorithms for audio communication products. The company also develops and markets the Eigenmike® and other associated microphone array systems. He is a fellow of both the Acoustical Society of America and the IEEE. He received the Acoustical Society of America’s Silver Medal in Engineering Acoustics in 2012 and the IEEE Signal Processing Society Industrial Innovation Award in 2015. He has more than 60 publications and over 30 patents in the area of acoustic transducers and acoustic signal processing.