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AES New York 2018

最新一届的AES大会将于2018年10月17日至20日在纽约举办。

会议官方链接:

http://www.aes.org/events/145/

AES全称Audio Engineering Society，音频工程协会，是目前音频以及声学行业影响里最大的组织。

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部分内容

会议涉及的方面非常多，包括扬声器，耳机，音箱，传声器(麦克风)，音频应用，信号处理，心理声学，录音，空间声学等等很多。

就现在能看到的会议日程来说，我个人非常感兴趣的部分有:

  • P04-1 Numerical Optimization Strategies for Acoustic Elements in Loudspeaker Design—Andri Bezzola, Samsung Research America - Valencia, CA USA
    Optimal design of acoustic loudspeaker design elements, such as waveguides and phase plugs, often requires extensive experience by the designer. Numerical simulations and optimization algorithms can aid in reducing the design-test-optimize cycle that is traditionally applied. A general mathematical framework for numerical optimization techniques is introduced and three algorithms of design optimization are reviewed: parameter optimization, shape optimization, and topology optimization. This paper highlights strengths and drawbacks of each method with the use of real-world design of a waveguide and two phase plugs. Where possible, the results are confirmed with prototypes and measurements. The work shows that excellent results can be achieved in just one design iteration with the help of numerical optimization methods. 
    Convention Paper 10046

Andri Bezzola是来自三星美国音频实验室的工程师。介绍了利用数值优化方法对扬声器系统中的声学元件，比如波导，相位塞等进行优化的方法。常用的设计优化算法包括参数优化，形状优化和拓扑优化。

  • P04-2 An Acoustic Model of the Tapped Horn Loudspeaker—Marco Berzborn, RWTH Aachen University - Aachen, Germany; Michael Smithers, Dolby Laboratories - McMahons Point, NSW, Australia
    A lumped-parameter model of the Tapped Horn loudspeaker–a design where the loudspeaker driver radiates into the throat as well as the mouth of the horn simultaneously–is presented. The model enables the estimation of the far-field sound pressure response from the Thiele/Small parameters of the loudspeaker driver and an additional analytic two-port matrix representation of the Tapped Horn. Simulations, performed using the model for subwoofers, are compared to measurements from an actual loudspeaker. 
    Convention Paper 10047

  • P04-5 Horn Driver Based on Annular Diaphragm and the Side-Firing Compression Chamber—Alexander Voishvillo, JBL/Harman Professional Solutions - Northridge, CA, USA
    This work proposes a new type of compression driver based on an annular flexural diaphragm and a topology that combines part of the diaphragm radiating directly into the horn and the other part loaded by a side-firing compression chamber. This configuration’s design is very simple compared to its predecessors. Acoustical theory, numerical simulations, matrix electrical-mechanical-acoustical model, and the results of real transducer measurements substantiate the new design. The new driver provides performance on par with more complex transducers of a similar format. 
    Convention Paper 10050 

Alex是JBL Pro的杰出工程师(Distinguished Engineer)。本次论文和演讲将分享一种新的环状压缩高音设计。

  • P04-6 On the Efficiency of Flown vs. Ground Stacked Subwoofer Configurations—Etienne Corteel, L-Acoustics - Marcoussis, France; Hugo Coste Dombre, L-Acoustics - Marcoussis, France; Christophe Combet, L-Acoustics - Marcoussis, France; Yoachim Horyn, L-Acoustics - Marcoussis, France; François Montignies, L-Acoustics - Marcoussis, France
    Modern live loudspeaker systems consist of broadband sources, often using variable curvature line sources, combined with subwoofers. While it is common practice to fly the broadband sources to improve energy distribution in the audience, most subwoofer configurations remain ground-stacked because of practical constraints and alleged efficiency loss of flown configurations. This article aims at evaluating the efficiency of flown subwoofers for large audiences as compared to their ground-stacked counterparts. We use finite element simulations to determine the influence of several factors: baffling effect, trim height. We show that flown configurations remain efficient at the back of the venue while reducing the SPL excess at the front of the audience. 
    Convention Paper 10051

  • P06-1 On the Interdependence of Loudspeaker Motor Nonlinearities—Finn T. Agerkvist, Technical University of Denmark - Kgs. Lyngby, Denmark; Franz Heuchel, Technical University of Denmark - Kgs. Lyngby, Denmark
    Two of the main nonlinearities in the electrodynamic loudspeaker are the position dependence of the force factor, Bl, and the voice coil inductance, Le. Since they both are determined by the geometry of the motor structure, they cannot be independent. This paper investigates this dependence both analytically and via FEM simulations. Under certain simplifying assumptions the force factor can be shown to be proportional to the spatial derivative of the inductance. Using FEM simulations the implications of this relation is illustrated for drivers with more realistic geometry and material parameters. 
    Convention Paper 10058 

    基于有限元分析，论述了力因子BL和音圈电感Le相互之间的依赖性。

  • P06-4 Evaluation of Efficiency and Voltage Sensitivity in Horn Drivers—Alexander Voishvillo, JBL/Harman Professional Solutions - Northridge, CA, USA; Brian McLaughlin, Harman Professional - Northridge, CA, USA
    There is a belief in horn driver design that if the resistive component of the input impedance of the diaphragm’s acoustical load is equal to the DC component of the voice coil’s electrical impedance, a maximum efficiency of 50% can be reached. This work shows that in reality, the compression driver’s real efficiency differs from the classical theory prediction. The discrepancy is explained by the fact that the driver’s output impedance and the acoustical loading impedance are different functions, not mere resistances. Additionally, the input electrical power and the output acoustical power are essentially integral functions of frequency and can be expressed by single numbers rather than frequency-dependent functions. Examples illustrating dependence of efficiency and sensitivity on various parameters are given. 
    Convention Paper 10061

仍然是Alexander Voishvillo的汇报。重新评估了号角扬声器的效率和灵敏度。

  • P06-5 Characterization of Nonlinear Port Parameters in Loudspeaker Modeling—Doug Button, Harman International - Northridge, CA, USA; Russ Lambert, Harman International - Richardson, TX, USA; Pascal Brunet, Samsung Research America - Valencia, CA USA; Audio Group - Digital Media Solutions; James Bunning, Harman International - Northridge, CA, USA
    The outputs from ports used in common vented box loudspeakers are not linear with input level. With the goal of developing accurate modeling of vented boxes, a new method for estimation of nonlinear port parameters is shown. Acoustic mass and acoustic resistance parameters change with pressure in the enclosure and velocity in the port. Along with all nonlinear speaker parameters required for modeling, a practical way to characterize the changing acoustic mass and acoustic resistance is presented and tested with measurements. Using the new method, nonlinear port parameters are extracted for multiple box and port types. 
    Convention Paper 10062

Doug Button展示了一种估计倒相管非线性参数的新方法。

  • PD10  Designing Hardware and Software Components in Modern Loudspeaker Systems——Wolfgang Klippel, Klippel GmbH - Dresden, Germany

    Modern loudspeakers use digital signal processing to generate more output with less energy and optimized hardware while coping with signal distortion, instabilities, overload, aging, climate, and other external influences. The control software provides self-learning capabilities and valuable diagnostic information that simplifies the selection of hardware components, integration in an active system, and assessing the performance of the product in the target application. The tutorial explains essential technical characteristics, the physical background, and practical simulation tools to exploit the new opportunities in optimized amplifier and transducer design.

Klippel教授将会介绍设计和优化扬声器系统涉及到的硬件和软件。

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国际交流

AES大会上精彩的内容很多，大牛也很多。国内的同行参与非常少，说实话是件很可惜的事。原因呢可能也有很多吧。

很遗憾，我也一直没能现场参与过AES大会。从明年开始，我会争取多参加国际间的交流。

这届AES大会上有价值的前沿研究，我会适当给大家做些分享。敬请期待。

上面是我的个人微信，加我的时候请表明身份，注明来意。