Sound-field intensity can be analyzed by measuring sound pressure and particle velocity. This study examines a previously proposed c–c method, in which the sound pressure and particle velocity can be measured using cardioid microphones. This method was validated for both far and near sound fields. However, to be considered as a viable alternative to the conventional p-p and p–u methods, the c–c method must also be validated in complex sound fields containing interfering sound waves. In our previous study, we took measurements by rotating a single microphone. This study aimed to further validate the c–c method using a pair of face-to-face cardioid microphones by conducting experiments in complex sound fields. The experimental results show that the sound pressure, particle velocity, complex intensity, active intensity, and reactive intensity measurements obtained in interference sound fields using the c–c method corresponded well with those obtained using the p–u probe. These results demonstrate that the c–c method can be applied to complex sound fields, including interference sound fields, and that a sound intensity probe can be constructed using a pair of cardioid microphones even if their cardioid directivities are not ideal.
Hanyu et al. (Thu,) studied this question.