社区低频声环境的自然声混合掩蔽研究

Study of Natural Sound Mixed Masking on Low Frequency Acoustic Environment in Community

为了应对无法消除的社区低频声环境影响,声掩蔽技术被用来提高区域声环境的主观感受。为此,该研究以自然声信号为掩蔽信号,通过主观评价试验分别探究了单独和混合自然声掩蔽对低频声环境质量的改善效果和影响因素。首先通过主观评价试验筛选出了具有良好掩蔽效果的流水声、鸟鸣声和树叶摩擦声,然后将流水-鸟鸣和流水-树叶摩擦声按不同的能量比例进行两两混合并进行了掩蔽试验。研究结果表明,同等声压级下的混合掩蔽效果与自然声能量占比呈显著的线性相关,即适当提高掩蔽效果更好的自然声信号能量比例,能够提高混合掩蔽的掩蔽效果。混合掩蔽声的等效连续响度与混合掩蔽效果之间存在显著的线性关系。非声学因素研究表明,性别对掩蔽效果没有显著的影响,而耳机使用频率对掩蔽效果存在显著的影响。

Nowadays,in order to deal with irreducible low frequency acoustic environmental impacts of the community,sound masking technology is usually considered to improve the subjective feeling of community sound environment.For this reason,the natural sound signals were taken as the masking signals.The improvement effect and influencing factors of single and mixed natural sound masking on the quality of the low frequency acoustic environment were explored by subjective evaluation experiments.Firstly,the sounds of running water,birds singing and leaves rubbing were selected as masking signals through subjective evaluation test.Then the water-birdsong and water-leaf friction were mixed in pairs at different energy ratios to carry out masking research then.The results showed that there was a significant linear correlation between the acoustic energy proportion of each pure natural sound and the masking effect.That is,the masking effect of mixed masking can be improved by appropriately increasing the energy ratio of natural acoustic signal with better masking effect.It is also found that the equivalent loudness of mixed masking sound have significant linear relationship to the masking effect.The study of non-acoustic factors show that gender has no significant effect on the masking effect,while the frequency of earphone use has significant effect on themasking effect.