The decrease in the amplitude and resolution of seismic waves with depth, the so-called earth Q effects, can be conveniently defined in terms of frequency-dependent amplitude attenuation and velocity dispersion. In this paper, we modify Kolsky's (1953 Stress Waves in Solids (Oxford: Clarendon)) attenuation–dispersion model so that it has an accurate representation of the velocity dispersion within the seismic band. Such a modification may lead to at least two advantages: (1) an accurate phase correction in inverse Q filtering that follows, and (2) a good match to other earth Q models. The latter suggests that, when applying them to design an inverse Q filter, filtered seismic sections should in principle be comparable with each other.