为何总谐波失真（THD）是不够的：频率归一化失真 | Why THD Isn’t Enough: Frequency Normalized Distortion Measurement Seminar

近代换能器技术的发展，尤其是压电MEMS扬声器的出现，重新引发了对归一化失真（亦称频率归一化失真）的关注，因为该指标对于准确表征其性能至关重要。 归一化失真度测量算法由Listen公司总裁Steve Temme于1993年在Brüel & Kjær公司任职期间首次提出並发表了AES论文。尽管该技术自1996年起已应用于SoundCheck软件，并被工程师使用近三十年，但近期才引发广泛关注。这种关注度提升源于两大因素：行业日益重视测量结果与可听性的关联性（Listen长期将此列为优先事项），以及新型微型扬声器技术的出现——传统失真测量方法无法对其进行全面评估。 本次研讨会将首先阐释失真机制，并通过掩蔽曲线探讨测量结果与听觉感知之间的关联。随后我们将剖析标准化失真与传统方法的差异，阐明其对表征现代压电MEMS扬声器至关重要的原因。 Recent transducer development, particularly piezo-MEMS loudspeakers, have brought renewed attention to Normalized Distortion (also known as Frequency Normalized Distortion), because it is essential to accurately characterize their behavior. Normalized Distortion is a measurement algorithm first proposed in a 1993 AES paper by Listen president Steve Temme during his time at Brüel & Kjær. Although it has been available in SoundCheck since 1996 and used by some engineers for nearly 30 years, interest in the technique has surged recently. This renewed focus is driven both by the industry’s increasing emphasis on correlating measurements with audibility - an area Listen has long prioritized - and by the emergence of new microspeaker technologies that cannot be fully evaluated using conventional distortion measurements. In this seminar, we’ll first explain distortion mechanisms and talk about correlating measured results to what we hear using masking curves. We’ll then examine how normalized distortion differs from the conventional approach and show why it’s essential for characterizing modern piezo-MEMS loudspeakers. #audiotest #audiomeasurement #soundcheck #frequencynormalizeddistortion #normalizeddistortion