Open-sphere designs for spherical microphone arrays

Ilya Balmages, Boaz Rafaely

Research output: Contribution to journalArticlepeer-review

111 Scopus citations


Spherical microphone arrays have been studied for a wide range of applications, one of which is acoustic measurement and analysis. Since a minimal interaction between the array and the measured sound field is an advantage in this case, open-sphere arrays are preferable compared to rigid-sphere arrays. However, it has been shown that open-sphere arrays suffer from numerical ill-conditioning at frequencies which correspond to the nodal values of the spatial spherical modes with the result of excessive noise at these frequencies. A method for overcoming this problem using an open dual-sphere array is proposed in this correspondence and then investigated and compared to an array configured around a rigid sphere and an array composed of cardioid microphones. An optimal value for the ratio of the two spheres is derived, and simulation examples illustrating the advantage of the dual-sphere array are finally presented.

Original languageEnglish
Article number4067021
Pages (from-to)727-732
Number of pages6
JournalIEEE Transactions on Audio, Speech and Language Processing
Issue number2
StatePublished - 1 Feb 2007


  • Array processing
  • Open-sphere array
  • Spherical Fourier transform
  • Spherical microphone arrays

ASJC Scopus subject areas

  • Acoustics and Ultrasonics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Open-sphere designs for spherical microphone arrays'. Together they form a unique fingerprint.

Cite this