扬声器音圈

Back in the Gold age of sound reproduction, an electromagnet was the only means of providing a magnetic field to the voice coil of an electrodynamic loudspeaker driver for sound reproduction, until the permanent magnet made it's appearance, it was a great idea back then to replace those bulky and expensive power supplies to feed the electromagnet coils, but something very subtle happened to the sound quality!

早在黄金年龄的声音复制，电磁铁是唯一的手段，提供了一个磁场对音圈的电动扬声器声音驱动程序的复制，直到永久磁体它的外观，它是一个伟大的想法，以取代当时那些笨重而昂贵的电源供应系统，饲料的电磁铁线圈，而是发生在非常微妙的音质！

Thermal behaviour of the woofers voice coil.

热行为的音圈低音扬声器。

After take analyzed deeply for the opened magnet circuit with FEMM (Finite Element Method Magnetics) we find out the field distributing that is separated into three sections . One is the main area what we called as positive field section. Beside the main field there are tow areas that are called the inverted field sections. Loudspeaker arise a very serious distortion when the voice coil moving into inverted field areas. The direction of induced current in the coil part of entered inverted field area is same with the current driving into loudspeaker so that total currents increas largely and heat increase rapidly. With more coils moving into inverted area the voice coil will take on negative inductance properties. It is the main reason that voice coil is burned by heating with increasing current due to arise negative inductance. So opened magnetic circuit is not suitable for the woofers in which the voice coil have wider displacement range. When using this kind magnetic circuit design, the voice coil moving range should be less than the range of positive field to avoid loudspeaker arise serious distortion and heating. Even though voice coil moving range is in the positive area, loudspeaker will still arise more distortion because the field distribution is very cliffy at tow sides of the positive area and full range of magnetic field distribution is not parallel that will arise distortion. Base on above reasons, opened magnetic circuit is not an ideal magnetic circuit for low-frequency loudspeakers. But it can be used in mid-range or high-frequency productions.

开式磁路是由2片钕铁硼磁铁和主导磁板和导磁垫片组成，我们在实践过程中发现这种磁路结构不适合于低频扬声器的使用，我们通过使用FEMM（Finite Element Method Magnetics）软件包对该磁路进行了分析，该磁路的磁场范围被分成3个区域，其中在主导磁板附近形成一个正向磁场，在正向磁场的两边存在反向的磁场，音圈在工作时有很大一部分进入了反向磁场中，在反向磁场内线圈的感应电流方向与驱动电流方向相同，使得音圈呈现出负感抗特性，由于音圈的负感抗特性引起电流的增加导致音圈发热甚至烧毁，因此在扬声器中使用开式磁路时，音圈的运动范围应控制在正向磁场范围之内，否则音圈运动到反向磁场区域时将会产生很大的失真和发热，即使在设计时已经将音圈的运动范围控制在正向磁场范围之内，由于正向磁场的2个边缘磁场强度衰减太快，同时开式磁路中磁场的分布不是平行的，而是自由发散的分布，这样肯定会导致扬声器的非线性失真，因此我们得到的结论是：开式磁路并不是一个理想的磁路，它不适合于低频扬声器的使用，但它还可以应用于中高频扬声器。

The opened magnetic circuit is composed as tow NdFeB permanent magnets and a top plate without U-yoke. After take analyzed deeply for the opened magnet circuit with FEMM (Finite Element Method Magnetics) we find out the field distributing that is separated into three sections . One is the main area what we called as positive field section. Beside the main field there are tow areas that are called the inverted field sections. Loudspeaker arise a very serious distortion when the voice coil moving into inverted field areas. The direction of induced current in the coil part of entered inverted field area is same with the current driving into loudspeaker so that total currents increas largely and heat increase rapidly. With more coils moving into inverted area the voice coil will take on negative inductance properties. It is the main reason that voice coil is burned by heating with increasing current due to arise negative inductance. So opened magnetic circuit is not suitable for the woofers in which the voice coil have wider displacement range. When using this kind magnetic circuit design, the voice coil moving range should be less than the range of positive field to avoid loudspeaker arise serious distortion and heating. Even though voice coil moving range is in the positive area, loudspeaker will still arise more distortion because the field distribution is very cliffy at tow sides of the positive area and full range of magnetic field distribution is not parallel that will arise distortion. Base on above reasons, opened magnetic circuit is not an ideal magnetic circuit for low-frequency loudspeakers. But it can be used in mid-range or high-frequency productions.

开式磁路是由2片钕铁硼磁铁和主导磁板和导磁垫片组成，我们在实践过程中发现这种磁路结构不适合于低频扬声器的使用，我们通过使用FEMM（Finite Element Method Magnetics）软件包对该磁路进行了分析，该磁路的磁场范围被分成3个区域，其中在主导磁板附近形成一个正向磁场，在正向磁场的两边存在反向的磁场，音圈在工作时有很大一部分进入了反向磁场中，在反向磁场内线圈的感应电流方向与驱动电流方向相同，使得音圈呈现出负感抗特性，由于音圈的负感抗特性引起电流的增加导致音圈发热甚至烧毁，因此在扬声器中使用开式磁路时，音圈的运动范围应控制在正向磁场范围之内，否则音圈运动到反向磁场区域时将会产生很大的失真和发热，即使在设计时已经将音圈的运动范围控制在正向磁场范围之内，由于正向磁场的2个边缘磁场强度衰减太快，同时开式磁路中磁场的分布不是平行的，而是自由发散的分布，这样肯定会导致扬声器的非线性失真，因此我们得到的结论是：开式磁路并不是一个理想的磁路，它不适合于低频扬声器的使用，但它还可以应用于中高频扬声器。

In addition, the speaker voice coil skew, speakers deviate from the core or magnetic gap are all sorts of things, speaker cone deformation, fed to the power amplifier may also result in excessive distortion.

此外，扬声器音圈歪斜、扬声器铁心偏离或磁隙中有杂物、扬声器纸盆变形、放大器馈给功率过大也会造成失真。

Speakers import modules with a combination of : titanium membrane Treble, and with fiberglass trumpet, better high frequency extension stronger sense of space; Bass modules using imported pulp Senate carbon fiber, rigid speaker cone greatly strengthened, the effective bandwidth within a more flat frequency response and bass modules using aluminum frame and aluminum wire voice coil. Shaker skeleton of the United States military material, light weight, high efficiency, so that the audio sound pressure increased significantly. more males, bass magnetic circuit using high efficiency of the cooling system to ensure that the speakers have very good heat dissipation, reduce distortion, effectively reduce the power to the compression.

跟进口喇叭单元的结合：采用钛膜高音，配以玻璃钢号角，使高频得到更好的延伸，空间感更强；低音单元采用进口纸浆参碳纤维，纸盆刚性大大加强，在有效的频宽内有更平坦的频率回应，低音单元采用铝盆架和铝扁线音圈，音圈骨架为美国军事物料制造，品质轻，效率高，使音频的声压大幅度提高，更具爆发力，低音磁路采用高效率的冷却系统，保证了扬声器有很好的散热，减少失真，有效降低功率的压缩给。

Voice Coil Motor is a special type of linear electric machinery, which is similar to thevoice coil of loudhailer in work principle.

音圈电机(Voice Coil Motor，简称VCM)是特种直线电机，其工作原理与扬声器的音圈类似。

The monitor EDGE15CXPB is a highly efficient 2 way low profile system. The bass frequencies are reproduced by a high excursion 15" woofer with a 4" voice coil. The woofer is equipped with a copper ring on the pole piece to achieve the lowest distortion in the critical vocal range.

EDGE15CXPB 是一个高效率的二分频紧凑型多功能返送扬声器，低频采用15英寸远射程单元配备 4 英寸音圈，这种低频单元在中心极上装配有铜圈，可将语音频段的失真降到最低。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。