GB/T 25102.2-2010 in English

《GB/T 25102.2-2010电声学 助听器 第2部分：具有自动增益控制电路的助听器》由TC23（全国电声学标准化技术委员会）归口，主管部门为工业和信息化部（电子）。

Scope

This part specifies the dynamic operating characteristics and steady-state operating characteristics of hearing aids with automatic gain control and their measurement methods. This part only stipulates various characteristics and related measurement methods, and does not specify various performance indicators. This section applies to all types of hearing aids with automatic gain control circuits. This standard includes devices having a compression or limiting function on the envelope of the input signal, and also includes devices with long-term average output control. a) The automatic gain control circuit is used to compress or reduce the dynamic range of the output sound pressure to maintain the integrity of the output signal. b) An automatic gain control circuit is usually used instead of a peak clipping device for limiting. When the input signal is large, the input/output characteristics tend to be flat. The main function of the limiting device is to prevent the excessive sound output by the hearing aid from entering the listener's ear. This section does not include: a) Extenders. b) Limiting device. The limiter is different from the automatic gain control circuit, the limiter cuts off the signal peak above a certain level. The automatic gain control circuit can keep the input signal waveform unchanged in steady state.