本文探討液晶電視喇叭單體因聲壓激振的影響，而產生結構共振異音問題，並尋找解決方案。由於液晶電視前後框之結合組裝是透過螺絲與塑膠卡勾進行組合並無法完全緊密結合，因此當喇叭單體在使用者播放各種影音聲效時，在低音或高頻音的變化上往往使前後框因聲壓之激振而產生碰撞造成結構共振異音。本文主要針對喇叭單體所產生之聲壓透過麥克風取得聲壓傳遞之共振頻率響應，並結合加速規取得液晶電視前後框之振動共振頻率，從而分析喇叭單體在不同硬度之隔振墊特性下所產生的隔振效果，進而找出最佳之喇叭單體隔振墊設計來隔絕喇叭單體共振聲壓之傳遞，並有效降低系統響應頻率而減少因結構共振異音而產生的惱人噪音問題。 This article is to study the TFT LCD TV’s loudspeaker from the sound pressure to cause the sound structure vibration and to look the solution for reducing the resonance noise. Due to the TV plastics front cover couldn’t be totally combine with the plastics rear cover and TFT-LCD panel, so it will collide with the TFT-LCD panel and case then emerge the vibration when the loudspeaker working. Especially input the sine sweep signal during 50~500Hz frequency to loudspeaker, the resonance structure noise will appear on the plastics cover. This experiment is to analysis the isolation material of the rubber and application to loudspeaker’s suspension. By way of the vibration shaker to arouse the loudspeaker model and used the accelerometer to find the isolation nature frequency (Fn). After comparison different hardness isolation and sponge resonance frequency on loudspeaker. To find the optimization design and actual assembly to TV system. The after solution TV system by NTI RT-2M resonance audio analysis verification, the structure resonance noise obtains more efficacious improved and the structure vibration also reduces.
