吉它弦乐结构声振特性的实验分析

Experimental Analysis of Vibration & Acoustic Characteristics of Guitars

基于结构实验模态分析及频谱分析技术 ,针对国产MG牌吉它进行了结构固有振动特性、弹奏声频谱特性的研究 .研究结果表明 ,实验吉它琴身前主要几阶固有振动频率符合或接近于理想吉它的设计要求 ,而其固有模态振型则与要求相差悬殊 ;当琴身结构固有振动频率与琴弦振动频率耦合时 ,弦振声易产生声波持续时间长、且具有和弦音的效果 .

Based on the experimental modal analysis (EMA) and spectrum analysis, the dynamic characteristics and sound spectrums of the MG guitar, made in China, are studied. It is shown from analysis results that the first few natural frequencies of the MG guitar accord with the ideal structure of guitar, but there obvions great differences between their modal modes. The playing sound of guitar will persist a long time and provide chord tone when the natural frequency of guitar structure couples well with that of the strings.