Table 2.

Measured acoustic properties of gel wax, in which the only additive was glass spheres. Each property (mean  ±  standard deviation) was obtained from measurements from five distinct regions. Acoustic attenuation as a function of frequency (f) was well described by the power law (${\alpha }_0{f}^n$), with parameters obtained from non-linear least squares fitting.

Glass spheres concentration (w/w%)	Acoustic attenuation ${\alpha }_0{f}^n$ (dB cm−1)		Speed of sound cs (m s−1)
	${\alpha }_0$	$n$
0	0.111  ±  0.013	1.80  ±  0.07	1445.7  ±  0.7
0.05	0.108  ±  0.012	1.83  ±  0.05	1443.9  ±  0.6
0.1	0.102  ±  0.005	1.87  ±  0.06	1443.5  ±  0.7
0.5	0.106  ±  0.028	1.88  ±  0.11	1443.4  ±  0.3
0.9	0.113  ±  0.009	1.87  ±  0.05	1444.1  ±  0.8