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The distance of microphones in sound intensity probe have great relations with effective sound frequency band measured during measuring sound intensity,. To adapt different measured frequencies, the position of every microphone in sound intensity probe should be adjusted. On the basis of discussing the theory of measuring sound intensity with four microphones from three dimensions, using the theory about keeping place of brace framework and parallelogram, we designed a new 3D sound intensity probe including four microphones. Because space among different microphones in sound intensity probe can be adjusted, it can choose appropriate measurement bandwidth according to the range of sound frequencies measured actually. 3D sound intensity probe with four microphones, whose measurement frequency can de adjusted, retained original advantages of 3D sound intensity probe, and overcome the shortcomings of measuring fixed bandwidth.

Double tree after wavelet transform has good direction selectivity and invariant parallel movement. Based on analysing histogram of modulus sub-band corresponding to six high frequency sub-band after double tree wavelet decomposition, we put forwaord a new kind of subtle character, namely combination character of Lognormal distribution parameters and Gamma distribution parameter. Using the character to segment signal feature, and using edge smooth technology in the process of segmentation and using k-means clustering to realize unsupervised segmentation. Experiments show that the method of feature extraction is new, and edge accuracy of segmentation results and regional consistency has antinoise character, and it is a kind of effective subtle segmentation method.