Abstract Smartphones have evolved into powerful devices with computing capabilities that rival the power of personal computers. Any smartphone can now be turned into a sound-measuring device because of its built-in microphone. Many sound measuring apps exist on the market for various mobile platforms. In our earlier research, we showed that a smart device with an adequate app can achieve compliance with most of the Class 2 requirements for periodic testing. In this paper, we present the methods and results of measuring directional response of a sound level meter consisting of a smartphone and one commercially available sound level meter app in the horizontal plane. We used both the built-in smartphone microphone and an external microphone according to relevant IEC [International Electrotechnical Commission] and ANSI [American National Standards Institute] sound level meter standards. The results show that the sound level meter app and an external microphone can achieve compliance with the requirements for Class 2 of IEC 61672/ANSI S1.4–2014 standard in the horizontal plane.

中文翻译：

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基于智能手机的声级测量应用程序：定向响应评估

摘要 智能手机已发展成为功能强大的设备，其计算能力可与个人电脑相媲美。由于其内置麦克风，任何智能手机现在都可以变成声音测量设备。市场上存在许多适用于各种移动平台的声音测量应用程序。在我们早期的研究中，我们表明配备足够应用程序的智能设备可以满足大多数 2 类定期测试要求。在本文中，我们介绍了测量由智能手机和一个市售声级计应用程序组成的声级计在水平面上的方向响应的方法和结果。根据相关的 IEC [国际电工委员会] 和 ANSI [美国国家标准协会] 声级计标准，我们使用了内置智能手机麦克风和外置麦克风。结果表明，声级计应用程序和外部麦克风可以在水平面内达到符合 IEC 61672/ANSI S1.4–2014 标准的 Class 2 要求。