會議室音響設備中的話筒通常按它轉換能量的方式分類。這里我們還是按錄音室對話筒通用的分類法,把話筒分為動圈話筒和電容話筒。
Microphones in conference room audio equipment are usually classified according to the way they convert energy. Here, we still divide microphones into dynamic microphones and condenser microphones according to the most common classification of microphones in recording studios.
動圈話筒:由磁場中運動的導體產生電信號的話筒。是由振膜帶動線圈振動,從而使在磁場中的線圈感應出電流。特點:結構牢固,性能穩定,經久耐用,較低;頻率特性良好,50-15000Hz頻率范圍內幅頻特性曲線平坦;指向性好;無需直流工作電壓,使用簡便,噪聲小。
Dynamic microphone: a microphone that generates an electrical signal from a conductor moving in a magnetic field. The vibrating membrane drives the coil to vibrate, so that the coil in the magnetic field induces current. Features: firm structure, stable performance, durability and low price; Good frequency characteristics, flat amplitude frequency characteristic curve in the frequency range of 50-15000hz; Good directivity; No DC working voltage, easy to use and low noise.
電容話筒:這類話筒的振膜就是電容器的一個電極,當振膜振動,振膜和固定的后極板間的距離跟著變化,就產生了可變電容量,這個可變電容量和話筒本身所帶的前置放大器一起產生了信號電壓。
Condenser microphone: the diaphragm of this kind of microphone is an electrode of the capacitor. When the diaphragm vibrates, the distance between the diaphragm and the fixed rear plate changes, resulting in variable capacitance. This variable capacitance and the preamplifier carried by the microphone generate signal voltage together.
特點:頻率特性好,在音頻范圍內幅頻特性曲線平坦,這一點優于動圈話筒;無方向性;靈敏度高,噪聲小,音色柔和;輸出信號電平比較大,失真小,瞬態響應性能好,這是動圈話筒所達不到的優點;工作特性不夠穩定,低頻段靈敏度隨著使用時間的增加而下降,壽命比較短,工作時需要直流電源造成使用不方便。
Features: good frequency characteristics, flat amplitude frequency characteristic curve in the audio range, which is better than dynamic microphone; Non directionality; High sensitivity, low noise and soft tone; The output signal level is relatively large, the distortion is small, and the transient response performance is good, which is an advantage that dynamic microphone can not achieve; The working characteristics are not stable enough, the low-frequency sensitivity decreases with the increase of service time, and the service life is relatively short. DC power supply is required during operation, resulting in inconvenient use.
電容話筒中有前置放大器,當然就得有一個電源,由于體積關系,這個電源一般是放在話筒之外的。除了供給電容器振膜的極化電壓外,也為前置放大器的電子管或晶體管供給必要的電壓。我們稱它為幻象電源。
If there is a preamplifier in a condenser microphone, of course, there must be a power supply. Due to the volume, this power supply is usually placed outside the microphone. In addition to supplying the polarization voltage of the capacitor diaphragm, it also supplies the necessary voltage to the electron tube or transistor of the preamplifier. We call it phantom power.
由于有了這個前置放大器,所以電容話筒相對要靈敏一些,在使用時不可少的一些附屬設 備有:防震架(一般會隨話筒贈送)、防風罩、防噴罩、的話筒架。如果要進行超近距離的錄音工作,一個防噴罩是不可少的。
With this preamplifier, the condenser microphone should be relatively sensitive. Some indispensable auxiliary equipment in use include: shockproof frame (usually presented with the microphone), wind shield, blowout preventer and high-quality microphone frame. A blowout preventer is indispensable for ultra close recording.
Today's highlights are shared here. For more highlights, please click our website: Shandong stage lighting and sound http://www.zkvd.cn , we will have a lot of content for you