Temporal and spectral analyses of decorative noises in Chinese Pipa music generated via Merge, Twist, Refrain and Flap skills

Pipa is a short-necked, normally four-stringed Chinese lute with a shallow, pear-shaped body. Noises can be conveniently generated from Pipa and are very often used as decorative components for improved perceptual experience. A few episodes from classic Chinese Pipa songs with decorative noises played using Merge, Twist, Refrain, and Flap skills were selected, played, and recorded for comparative studies. The episodes were also played and recorded without the decorative noises. Temporal and spectral analyses were conducted to evaluate the two versions, with and without the decorative noises, respectively. The difference between the two versions was analyzed and illustrated. The intensity profiles of the decorative noises were correlated with those of their contexts for rhythmic harmony evaluation. The positive effects of adding decorative noises to the selected episodes of Pipa music were confirmed based on the findings of the comparative studies.