  The human sense of hearing perceives a combination of sounds 'in tune' if the
corresponding harmonic spectra are correlated, meaning that the neuronal
excitation pattern in the inner ear exhibits some kind of order. Based on this
observation it is suggested that musical instruments such as pianos can be
tuned by minimizing the Shannon entropy of suitably preprocessed Fourier
spectra. This method reproduces not only the correct stretch curve but also
similar pitch fluctuations as in the case of high-quality aural tuning.
