Long-Term Average Spectra (LTAS) of scales recorded on the Test Violin and the two Control Violins. The left column displays the average across the Control Group (10 violinists), while the right column displays the Test Violinist. Black curves indicate the “Before” phase and gray curves indicate the “After” phase; the Pearson correlation coefficient between these two states is provided in the bottom-left corner of each panel. The bottom panel displays the mean LTAS magnitude difference between the “Before” and the “After” phases. For the Control Group, shaded areas represent the 95% confidence interval.