通過揚聲器振膜位移測試頻響曲線
王琳娜
摘 要：目前大量使用的揚聲器在線測試系統，都是饋給待測揚聲器以激勵信號，揚聲器發聲，測試傳聲器拾取該聲音然后做分析，得到該揚聲器的電聲學特性。可實際車間里有諸多因素如機器噪聲、反射聲等都會影響最終的測試結果。該文通過另外一種方式，用激光測距傳感器測試揚聲器振膜的振動位移，然后反演出揚聲器的頻響曲線等信息。通過大量實驗得出：利用振膜位移曲線反演得到頻響曲線在低頻段可以和直接聲學測試的頻響曲線很好地擬合，同時振膜位移受周圍環境噪聲的影響較小，對環境依賴性較小，可以在生產線上應用。
關鍵詞：揚聲器；振膜位移；頻響曲線
中圖分類號：TN64；O329；TM935.23；TP274+.2 文獻標志碼：A 文章編號：1674-5124（2013）05-0031-03
Measure speaker’s frequency response curve via diaphragm’s excursion
WANG Lin-na1， JING Ni-qin1， WU Guo-qiao2
（1. Beijing Polytechnic，Beijing 100016，China；
2. North China Institute of Computing Technology，Beijing 100083，China）
Abstract: On-line measurement is mandatory in the speaker industry， so far the measurement processing is to feed the speaker electrical signal to make it generate sound， then the measurement microphone picks up the sound for analysis， get the electroacoustic parameters of the speaker. Actually there is a lot of noise and reflection in workshop. These affect the final measurement result. The article is trying to use another way， use laser displacement meter to measure speaker diaphrangm’s excursion， then calculate the speaker’s frequency response and other items. A lot of test results show the calculated frequency response curve via diaphragm’s excursion can match the measured frequency response curve well at low frequency range， and diaphragm’s excursion is less affected by ambient noise， less environment dependent， so can be applied in procuction lines.
Key words: speaker； diaphragm’s excursion； frequency response curve
