便携式多媒体设备电池持续时间的测定第2部分：具有主动降噪功能的头戴式耳机和入耳式耳机

[中文适用范围]： 本文件适用于具有通过环境噪声检测麦克风和降噪信号处理电路产生的换能器输出声音水平来减少用户听到的环境噪声功能的主动降噪耳机和耳塞。 本文件涵盖需佩戴在耳上或入耳的耳机和耳塞，在本文中统称为“耳机”。 本文件规定了与此类耳机电池续航相关的术语和定义以及测量和评估方法。 噪声检测麦克风安装在耳机本体、表面或配件上。信号处理电路包括模拟和数字电子电路。 本文件不涉及用于听力保护的设备，也不适用于具有降噪功能的音乐播放器、录音机等。 电池续航测量方法可应用于没有主动降噪功能的耳机。 [外文原描述]： IEC 63296-2:2023 is applicable to active acoustic noise-cancelling headphones and earphones that have the function of reducing the ambient noise heard by the user by the level of the output sound from the transducer, which is generated by the ambient noise detection microphone and the noise reduction signal processing circuit. This document covers headphones and earphones to be worn over-the-ear or in-ear, all of which are referred to as "headphones" in this document. This document specifies the terms and definitions relating to battery duration of this type of headphones and the measurement and evaluation methods. The noise-detection microphones are mounted in the body, on the surface, or on an accessory of the headphones. Signal-processing circuits are analogue and digital electronic circuits. This document does not deal with equipment intended for hearing protection. It is also not applicable to music players, recorders, etc. that have a noise-cancelling function. The battery duration measurement methods can be applied to headphones having no active noise-cancelling function.