Measurements of speeds of sound u have been made in binary mixtures of n-butanol (n-C4H9OH) with H-pentane (n-C5H12), or n-hexane (N-C6H14), or n-heptane (n-C7H16), or n-octane (n-C8H18), or 2,2,4-trimethylpentane (2,2,4-(CH3)(3)C5H9), or carbon tetrachloride (CCl4) at T=293.15 K. Values of u have been used to calculate the apparent excess speeds of sound Delta u and the isentropic compressibilities kappa(s) for these mixtures. The excess isentropic compressibilities kappa(S)(E) have also been calculated from the values of kappa s. The kappa(S)(E) values have been found to be highly negative for {xn-C4H9OH + (1 - x)n-C5H12}. The values of kappa(S)(E) have been found to be positive at lower mole fractions for n-C4H9OH, and negative at higher more fractions for {xn-C4H9OH + (1 - x)n-C6H14}, {xn-C4H9OH + (1 - x)n-C7H16}, {xn-C4H9OH + (1 - x)n-C8H18}, {xn-C4H9OH + (1 - x) 2,2,4-(CH3)(3)C5H9}, and {xn-C4H9OH + (1 - x) CCl4}. The inversion of sign in kappa(S)(E) occurs at x approximate to 0.20, x approximate to 0.54, x approximate to 0.77, x approximate to 0.23, and x approximate to 0.75, respectively, for these mixtures.