有源降噪入耳式耳机声衰减实验测量及对比研究

Experimental measurement and comparative study of sound attenuation measurement methods of active noise reduction insert earphones

针对有源降噪入耳式耳机声衰减测量,对比研究了4种典型的测量方法,包括真耳听阈衰减法(REAT)、等响法(LB)、真耳内置传声器法(MIRE)和专用声学测试装置法(ATF)。依据该类耳机的特点设计了测量装置、实验环境和实验方案,开展了3款耳机的测量研究。结果表明,对于无源声衰减测量, MIRE方法与作为护听器“黄金”标准的REAT方法相比,中高频差异在±3 dB范围内,而MIRE方法在低频更准确;对于有源声衰减测量, MIRE方法与LB方法的结果接近,差异在±2 dB范围内,且MIRE方法更易于操作。MIRE方法有较高的测试效率和准确性,是测量有源降噪入耳式耳机声衰减的一种有效方法。

For the measurement of sound attenuation of active noise reduction insert earphones,four typical measurement methods are comparatively studied,including real-ear attenuation at threshold(REAT),loudness balance(LB),microphone-in-real-ear(MIRE),and acoustic test fixture(ATF)methods.According to the characteristics of the earphones,the measurement devices,experimental environment,and experimental procedures are designed,and the measurement studies of three earphones are carried out.The results show that for passive sound attenuation measurements,the results of the MIRE method are close to those of the“gold”standard—REAT method in the middle and high frequency range,with a difference of±3 dB,and more accurate at low frequencies.For active sound attenuation measurements,the results of the MIRE and LB methods are close to each other,with a difference of±2 dB,and the MIRE method is easier to operate.The MIRE method has high test efficiency and accuracy and is an effective method to measure the sound attenuation of active noise reduction insert earphones.