Research on the quality evaluation of acoustic characteristics of lute audio signal based on the physical model of string vibration

Abstract:
As a national musical instrument, the sounding mechanism and acoustic characteristics of the lute is worthy of our indepth study, and there is a lack of relevant standards for quality evaluation. The main work of this thesis is to firstly study the string vibration of Lute, analyze ist error hull formula according to the principle of lute string vibration, and study the influence of different plucking positions on the fundamental frequency and harmonic frequency of Lute, and to discuss the relationship of the fundamental error of the lute musical instrument and the influence of different plucking states on the occurrence frequency ; secondly, calculate the vibration equation of Lute strings to get. We have recorded a large number of Lute signals and analyzed them in professional numerical signal analysis software, using a series of signal processing methods and MATLAB programs edited by ourselves to analyze lute audio signals. First, a series of preprocessing such as sampling, noise removal, predicted weighting, etc. are carried out for the collected pipa tone signal. Then the time domain analysis, frequency domain analysis, pitch detection and spectral centroid detection are carried out for the preprocessing sound signal. We can quantify the amount of information of these acoustic features to a certain extent, and preliminarily study the change of the acoustic characteristics of Lute, which is the follow-up theoretical research of Lute Lay the groundwork with process improvements. From these analyses and calculations, the objective physical parameters related to the sound quality of the pipa are found to establish a comprehensive discrimination system for the quality of the lute.