An earlier paper  made a comparison of two low-cost tetrahedral ambisonic microphones, an experimental microphone and a Core Sound TetraMic, using a Soundfield MKV or SPS422B as a standard for comparison. This paper examines improvements to the experimental device, including that suggested in the “future work” section of the original paper. Modifications to the capsules and a redesign of the electronics package made significant improvements in the experimental microphone. Recordings were made in natural environments and of live performances, some simultaneously with the Soundfield standard. Description of the recording process is included. Of interest is the use of the low-cost “do-it-yourself” surround microphone for student and experimental education.
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