《立体声原理》评述

高保真立体声是一门诱人的科学技术,它集中了现代放声技术的新成就,采用了声频工程中的一些新器件和新设备来满足人们欣赏音乐戏曲的音质要求.1981年由科学出版社出版、谢兴甫编著的《立体声原理》一书在发展立体声录音、立体声调频广播、立体声唱片和厅堂电声系统过程中,在普及家庭高保真立体声的浪潮中是一本有价值的参考书. 《立体声原理》全书约31万字,是按照立体声发展过程的顺序来编写的,它不但总结了国内外有关立体     

电声技术近年进展

本文讨论近年电声技术的进展，综述电声器件概况，介绍高保真立体声中的环境声和数字声频，并总结迅速发展的声场电声控制技术，最后讨论了主观电声测量方面的动态．     

立体声纵论

本文提出了立体声的科学分类和质量评价一种方法，并分析了数学信号处理技术的引入对立体声所产生的飞跃和问题。     

用普通物理眼光看立体声音响系统

本文用波动方程对立体声系统的研制进行了分析，对物理教学内容的改革进行了尝试，收到了较好的教学效果。     

通路相位差与立体声声像定位

考虑双耳根位差的高级近似，得到了具有更普遍意义的、重发通路间存在相位差时的立体声声像定位公式．在极低频或通路间相位差较小的情况下，它将简化为Makita理论的结果.但一般情况下声像位置将明显与频率有关．着重指出，在通路间存在相位差的立体声重发中，声像位置随频率而变化是导致声像展宽的主要原因．同时通路间相位差引起的附加低频对耳声级差是导致声像自然度降低的重要原因.在实际应用中，应尽量减少通路间的相位差，至少应减少到60°以下.     

平面环绕声场的研究

本文应用了环绕声场重发中的声像定位公式,普遍地探讨了(包括左、右对称和不对称)二个传输通路的矩阵型立体声系统。证明了它们重发时都不可能获得一个无声像位置畸变的平面环绕声场,因而肯定了一切4-2-4矩阵型立体声系统都不是完美的平面环绕声系统。 文中也指出采用三个传输通路的立体声系统能够在重发时产生无声像位置畸变的平面环绕声场,着重指出,三个独立传输信号的形式不是唯一的,给出了任意两组独立传输信号和所对应的两个不同的译码矩阵的变换关系。文中最后指出了选择独立传输信号形式时所应注意的问题。     

数字音响系统(二)

三、数字式唱片放声系统1．数字音频唱片由于PCM信号的频带很宽，要直接以PCM信号记录在唱片上需要有新的高密度记录方式．若PCM信号来样频率为45kHz，13bit，双通路，则要求带宽约为1．2MHz，是一般密纹唱片的规倍．若要记录四通路立体声信号，则要求2．4MHz带宽．因此采用可记录10MHz信号的激光视频唱片为记录媒质．七十年代发展的数字音频唱片（DAD）有机械式，静电式和激光式三类．机械式DAD最简单，刻纹和重放方式与普通唱片相似．放声时采用压电换能器，拾取波长为0．5μm的信号．解调后的数字音频信号经读码校正处理，由D…     

高保直立体声(Ⅰ)

一、引 言 高保真度(英文为High-Fidelity,简写为Hi-Fi)放声和立体声技术是声频工程师、电声科技人员和业余无线电爱好者都十分关心的问题.高保真立体声技术与广播、电视、电影、唱片和磁带录声等专业有极密切的关系.目前用电子学方法无畸变地记录和重发声音已经能够     

多通路声和家庭影院(1)

本文叙述了多通路声的发展和它的音质。环绕声系统和家庭影院的进展,将使家庭内具有甚优于目前流行的双通路立体声系统的音质。     

高保真立体声(Ⅲ)

双通路立体声 高保真双通路立体声的节目源有三类:调谐器、唱片和磁带.立体声调谐器接收调频广播的立体声节目.立体声唱片则把两路信息以机械能形式储存在槽纹中,声压的变化相应于唱片槽纹中线的位移,通过立体声电唱盘来重     

水声声强测量分析系统及其在水下噪声鉴别中的应用

本文将空气中能形成测量分析系统的声强测量技术引入到水介质中，建立了一套水声声强测量分析系统，讨论了此套水声声强测量分析系统的硬，软件组成及特征，实验验证了本系统的可靠性，利用此声强分析系统对水下双噪声源的近场作了平面扫描测量，可以定位和鉴别这两个噪声源。     

A simple impulse sound source for measurements in room acoustics

This paper deals with the construction and characteristics of a specially designed wooden clapper intended to operate as an impulse sound source for measurements in rooms. It is to be used as an alternative impulse sound source for experimental estimations of impulse responses of rooms located at remote and specific places where none of the standard sound sources - an omnidirectional loudspeaker system, etc. - can be used. The paper describes the spectral characteristics and directivity of the clapper impulse. Its features are compared with other impulse sources.     

Intratympanic manganese administration revealed sound intensity and frequency dependent functional activity in rat auditory pathway

The cochlear plays a vital role in the sense and sensitivity of hearing; however, there is currently a lack of knowledge regarding the relationships between mechanical transduction of sound at different intensities and frequencies in the cochlear and the neurochemical processes that lead to neuronal responses in the central auditory system. In the current study, we introduced manganese-enhanced MRI (MEMRI), a convenient in vivo imaging method, for investigation of how sound, at different intensities and frequencies, is propagated from the cochlear to the central auditory system. Using MEMRI with intratympanic administration, we demonstrated differential manganese signal enhancements according to sound intensity and frequencies in the ascending auditory pathway of the rat after administration ofintratympanicMnCl₂.Compared to signal enhancement without explicit sound stimuli, auditory structures in the ascending auditory pathway showed stronger signal enhancement in rats who received sound stimuli of 10 and 40 kHz. In addition, signal enhancement with a stimulation frequency of 40 kHz was stronger than that with 10 kHz. Therefore, the results of this study seem to suggest that, in order to achieve an effective response to high sound intensity or frequency, more firing of auditory neurons, or firing of many auditory neurons together for the pooled neural activity is needed.     

Sound image method and sound energy vortex in rectangular room

1.TntroductionMostprob1emsofsolvingsoundficlds,suchassoundpressuredistributionsinroomsareclassiia1.lllIn10wfrequencyrange,wavemotionmethodisapplied.Inthemethod,thenorma1modesofroomaresolvedandthensummeduptocvaluatetheirunknownamplitudesbymatchingsoundsource.Inhighfrequencyrange,thenumberofnormalmodesneedcdisnumer0usandtogetfina1solutionwouldbeimpossiblebecauseofthetimeconsumptionincomputation.Hence,ther0omacousticsbasedongeometri-calacousticsandthestatisticswasdevcloped.Thewavemotionmethodcan…     

频率对环绕声声像定位的影响

本文考虑双耳相位差的高级近似，导出了中频情况下适用的具有更普遍意义的平面环绕声声像定位公式。在低频时该式将化为通常的环绕声声像定位公式，而随着声音频率的增加，声像位置将与频率有关。将新的公式用到方型排列和棱型排列的４－４－４环绕声系统，得到了同实验相一致的结果。文中着重指出，声像随频率而变化是导致环绕声重发中侧向声像不稳定的重要在而为今后改进环绕声系统提供了理论基础。     

声强测量技术在水下结构辐射噪声近场测量中的应用

本文介绍了强测量技术在水下结构辐射近场测量中的实际测量系统，特别是水下声系统的扫描平面的实现方法及定位误差控制方法，最后讨论和分析了实际测量结果，从而说明该系统用水下声强测量是可行的。     

Factors influencing the sound preference in urban open spaces

In this paper, based on a large scale survey in Europe and China as well as corresponding laboratory studies, the influencing factors on the sound preference evaluation, considering social, demographical, physical, behavioural and psychological facets, have been systematically examined based on statistical analyses for each of the 19 case study sites. Various sound types have been considered, including natural, human, mechanical and instrumental sounds. In terms of social/demographical factors, the results suggest that age and education level are two factors which universally influence the sound preference significantly, although the influence may vary with different types of urban open spaces and sounds. With increasing age or education level, people tend to prefer natural sounds and are more annoyed by mechanical sounds in general. It has also been found that gender, occupation and residence status generally would not influence the sound preference evaluation significantly, although gender has a rather strong influence for certain sound types such as bird sounds, especially at certain case study sites. In terms of physical factors (season, time of day), behavioural factors (frequency of coming to the site, reason for coming to the site), and psychological factors (site preference), generally speaking, their influence on the sound preference evaluation is insignificant, except for limited case study sites and certain sound types. The influence of home sound environment, in terms of sounds heard at home, on the sound preference has been found to be generally insignificant, except for certain sounds. It is noted that there are some correlations between social/demographical factors and the studied physical/behavioural/psychological factors, which should be taken into account when considering the influence of individual factors on sound preference.     

Sound field prediction in long enclosures with branches: A combined method

The propagation of sound in long enclosures with branches has been studied theoretically and experimentally, and an efficient combined method is proposed to predict the sound field in long enclosures with branches. Based on the wave-acoustics theory, the theoretical analysis of the sound field of the long enclosures with branches is performed. This paper also investigated the sound field prediction of long enclosures with branches, by using the acoustic modeling program, ODEON. The results obtained by the theoretical analysis and the numerical simulation ODEON are compared with the experimental measurements, and the characteristics of the two methods for predicting the sound field of long enclosures with branches are analyzed. Compared with the experimental results, it is found that: (1) the results predicted by the theoretical analysis fluctuate relatively large with respect to the source-receiver distance, and the sound pressure level (SPL) attenuation obtained is smaller than that measured; and (2) the results predicted by the numerical simulation is smoother, and the calculated SPL attenuation is larger than that measured. To effectively predict the sound field of long enclosures with branches, a combined numerical method is thus proposed. The effectiveness of the proposed combined method is demonstrated by the scale-model experiments.