In the paper, the authors show, in relation to a test campaign carried out on brick masonry panels,  the importance of sonic test. Although this diagnostic test does not allow to obtain an high level of knowledge, according to the Circular n° 617 (February 2009) related to the Italian Technical Code (M.D. January 2008), the result of a correct application permits to characterize, in a quantitative way, some constructive details, very useful to determine the value of mechanical parameters to adopt in our safety checks. In particular, the carrying out of sonic test allows to individuate the presence of transversal connections inside the masonry (called in Italian “diatoni”) and subsequently to justify the use of corrective coefficient proposed in the Annex of the Circular n° 617 (February 2009).