Bai Mingsian R, Wen Jheng-Ciang, Hsu Hoshen, Hua Yi-Hsin, Hsieh Yu-Hao
Department of Power Mechanical Engineering, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan.
J Acoust Soc Am. 2014 Oct;136(4):1591-600. doi: 10.1121/1.4894693.
A sound reconstruction system is proposed for audio reproduction with extended sweet spot and reduced reflections. An equivalent source method (ESM)-based sound field synthesis (SFS) approach, with the aid of dark zone minimization is adopted in the study. Conventional SFS that is based on the free-field assumption suffers from synthesis error due to boundary reflections. To tackle the problem, the proposed system utilizes convex optimization in designing array filters with both reproduction performance and acoustic contrast taken into consideration. Control points are deployed in the dark zone to minimize the reflections from the walls. Two approaches are employed to constrain the pressure and velocity in the dark zone. Pressure matching error (PME) and acoustic contrast (AC) are used as performance measures in simulations and experiments for a rectangular loudspeaker array. Perceptual Evaluation of Audio Quality (PEAQ) is also used to assess the audio reproduction quality. The results show that the pressure-constrained (PC) method yields better acoustic contrast, but poorer reproduction performance than the pressure-velocity constrained (PVC) method. A subjective listening test also indicates that the PVC method is the preferred method in a live room.
本文提出了一种用于音频再现的声音重建系统，该系统具有扩展的最佳听音区域和减少的反射。本研究采用了一种基于等效源法（ESM）的声场合成（SFS）方法，并借助暗区最小化技术。基于自由场假设的传统SFS由于边界反射而存在合成误差。为了解决这个问题，所提出的系统在设计阵列滤波器时采用凸优化方法，同时考虑了再现性能和声学对比度。控制点部署在暗区，以尽量减少来自墙壁的反射。采用两种方法来约束暗区内的压力和速度。在矩形扬声器阵列的模拟和实验中，压力匹配误差（PME）和声学对比度（AC）被用作性能指标。音频质量感知评估（PEAQ）也用于评估音频再现质量。结果表明，压力约束（PC）方法产生的声学对比度更好，但再现性能比压力 - 速度约束（PVC）方法差。主观听觉测试还表明，在现场房间中，PVC方法是首选方法。
