Free-field sensitivity of four electro-acoustic measuring chains at 0° incidence angle in the frequency range 0.25 kHz to 100 kHz

This dataset contains calibration data of the free-field sensitivity of four electro-acoustic measuring chains at 0° incidence angle in the frequency range 0.25 kHz to 100 kHz. Each of the four channels consisted of a ¼'' externally polarized free-field measurement microphone of the condenser type GRAS 40 BF, a ¼'' preamplifier GRAS 26AC, a power module GRAS 12AQ and an FFT analyzer Ono Sokki CF-9400. The calibration data was acquired in the laboratory of the Physikalisch-Technische Bundesanstalt (PTB).本数据集包含四条电声测量链在0°入射角度、0.25 kHz至100 kHz频率范围内的自由场灵敏度校准数据。四条测量通道中的每一条均由1/4英寸外极化电容式自由场测量传声器GRAS 40 BF、1/4英寸前置放大器GRAS 26AC、功率模块GRAS 12AQ以及快速傅里叶变换（Fast Fourier Transform，FFT）分析仪Ono Sokki CF-9400组成。该校准数据采集自德国联邦物理技术研究院（Physikalisch-Technische Bundesanstalt，简称PTB）的实验室。