Abstract A centimetre-sized single grain of the perfect AlPdMn icosahedral phase can be grown by slow cooling from the liquid. This phase has been shown to have perfect icosahedral symmetry, i.e. without any frozen phason strain. The dynamical properties of this icosahedral phase have been studied by mean of inelastic measurements on triple axis spectrometers. The dispersion relations around several Bragg reflections were measured. Pseudo-zone boundaries can be defined, similarly to those previously obtained in the AlLiCu phase. A dispersionless optic mode was identified around 4 THz.