A recent survey of piano acoustics literature revealed an apparent lack of attention to various aspects of dispersion in piano strings, apart from some information on its effect on inharmonicity of piano tone partials. In this article, it will be shown how group velocity of transverse waves in piano strings can be measured as a function of frequency with the aid of a short-time spectral analysis method. Examples of group velocity measurements appear to be essentially in agreement with the theoretical predictions based on a model of a flexurally stiff string. In addition, the relationship between the group and phase velocity, as a function of frequency, is also illustrated, indicating correspondence between theoretical predictions and experimental results. A short-time spectral analysis of transverse string displacement as a function of time, monitored near the bridge, has revealed a quasiperiodic succession of frequency glides. This effect is due to dispersion and is particularly prominent in the lowest bass strings. However, the same type of analysis applied to the sound-pressure signal of the corresponding radiated sound yielded somewhat different results. While frequency glides similar to those found in the string displacement spectra were partly evident in the sound-pressure spectra, strong precursive components of longitudinal string vibration origin were found to dominate the higher frequency portion of the attack transient of the radiated sound.