Fréour Vincent, Gautier François, David Bertrand, Curtit Marthe
Université du Maine, LAUM, UMR CNRS 6613, Avenue Olivier Messiaen F-72085, Le Mans Cedex 9, France.
LTCI, CNRS, Télécom ParisTech, Université Paris-Saclay, 75013, Paris, France.
J Acoust Soc Am. 2015 Dec;138(6):3930-40. doi: 10.1121/1.4937749.
Guitar plucked sounds arise from a rapid input of energy applied to the string coupled to the instrument body at the bridge. For the radiated pressure, this results in quasi-harmonic contributions, reflecting the string modes coupled to the body, as well as some transient and quickly decaying components reflecting the excitation of the body modes of the instrument. In order to evaluate the relevance of this transient body sound, a high resolution analysis-synthesis method is described for the extraction of the body-mode contribution from the radiated pressure measured in the near field of the guitar top plate. This analysis scheme is first tested on synthesized signals. Some body-sound emergence indicators are then proposed and computed over a pool of instruments. The influence of the conditions of excitation on the body-sound emergence is investigated, and the instruments categorized according to these objective descriptors. Results show a larger range of body-sound emergence with variations of the plucking position in hand-made guitars compared to industrial instruments. This suggests that these particular hand-made instruments are more sensitive to variations in the control from the player and hence allow a wider range of timbres with respect to the transient coloration of the body modes.
吉他拨弦声源于在琴桥处施加于与琴身相连琴弦的快速能量输入。对于辐射压力而言，这会产生准谐波成分，反映与琴身耦合的弦模式，以及一些瞬态且迅速衰减的成分，反映乐器琴身模式的激发。为了评估这种瞬态琴身声音的相关性，本文描述了一种高分辨率分析合成方法，用于从吉他面板近场测量的辐射压力中提取琴身模式的贡献。该分析方案首先在合成信号上进行测试。然后提出了一些琴身声音出现指标，并在一批乐器上进行计算。研究了激发条件对琴身声音出现的影响，并根据这些客观描述符对乐器进行分类。结果表明，与工业乐器相比，手工制作的吉他在拨弦位置变化时，琴身声音出现的范围更大。这表明这些特定的手工制作乐器对演奏者控制的变化更敏感，因此在琴身模式的瞬态色彩方面能够产生更广泛的音色。
