A quantitative study on the influence of fingering variations on acoustic characteristics in guzheng performance

Guzheng timbre and expressive depth are closely determined by fingering techniques, since differences in string contact method, force direction, contact angle, and contact duration directly affect the time-domain and frequency-domain characteristics of the acoustic signal. However, traditional guzheng teaching and performance practice mainly rely on auditory experience rather than systematic acoustic evidence. This study focuses on four basic and widely used fingering techniques, namely gou, tuo, mo, and cuo. Under controlled conditions involving the same performer, instrument, pitch, and dynamic range, high-precision recordings are obtained in a professional recording environment. A total of 100 valid samples are analyzed, with 25 samples for each fingering technique. Acoustic features including energy envelope, attack time, decay time, spectral centroid, spectral roll-off, harmonic-to-noise ratio, and frequency-band energy distribution are extracted and analyzed using statistical tests and unsupervised clustering. Results show significant differences among the four techniques. The cuo technique presents the highest energy concentration, spectral centroid, and harmonic-to-noise ratio, while the mo technique shows broader frequency-band distribution, longer decay time, and lower harmonic-to-noise ratio. Clustering results confirm that the four fingering techniques are distinguishable in multidimensional acoustic feature space.