Experimentally based description of harp plucking

Abstract

This paper describes an experimental study of string plucking for the classical harp. Its goal is to characterize the playing parameters that play the most important roles in expressivity, and in the way harp players recognize each other, even on isolated notes--what we call the "acoustical signature" of each player. We have designed a specific experimental setup using a high-speed camera that tracks some markers on the fingers and on the string. This provides accurate three-dimensional positioning of the finger and of the string throughout the plucking action, in different musical contexts. From measurements of ten harp players, combined with measurements of the soundboard vibrations, we extract a set of parameters that finely control the initial conditions of the string's free oscillations. Results indicate that these initial conditions are typically a complex mix of displacement and velocity, with additional rotation. Although remarkably reproducible by a single player--and the more so for professional players--we observe that some of these control parameters vary significantly from one player to another.

Estimation of Guitar Fingering and Plucking Controls Based on Multimodal Analysis of Motion, Audio and Musical Score

“…of the 11th International Symposium on CMMR, Plymouth, UK, June [16][17][18][19]2015 Several improvements are foreseen for the future. (1) Develop an algorithm for pitch extraction from audio adapted to the guitar to avoid the use of a musical score; (2) build a 3D flexible object model of the hand and a hand motion grammar in order to restrict the possible positions of the flexible object and be able to reconstruct missing markers from the position and angles of the identified joints; (3) Use of a finger-tip model in order to calibrate the position of the real nail and flesh with respect to the marker; (4) The use of high speed video cameras to calibrate and evaluate data from the motion capture and deepen the analysis of the plucking process (start, contact and release) as done in Chadefaux et al (2012).…”

“…Heijink and Meulenbroek (2002) researched the complexity of left-hand classical guitar movements using an active optical motion capture system with four infrared light emitting diodes placed on the fingernails of the left hand, one on the left wrist, one each on the right index and middle fingers and three on the body of the guitar. Chadefaux et al (2012) used high speed video cameras to manually extract features during plucking of harp strings.…”

A model of harp plucking

“…The estimation of the finger and the string trajectories is performed by tracking markers, placed on finger and string at strategic places, through image processing. 1 More precisely, because we are interested in displacements referred to as x s , x f , z s , and z f in Fig. 1, markers are positioned as close as possible to the plucking position y 0 and to the nail, respectively.…”

“…( As the friction phenomenon in harp plucking occurs for normal forces always greater than 1 N, 1 we assume the relationship between F t and F n to be linear through a unique friction coefficient l. Figure 2 illustrates the plucking action during the slipping phase. The direction of the slipping is given by the angle c, which is controlled by the harpist.…”

“…The harp plucking can be split into two successive time phases: 1 The sticking and the slipping phases. The harp plucking modeling is structured accordingly.…”