Magnetic fluid speaker

The electroacoustic conversion efficiency of the electric paper disc speaker is very low, generally not exceeding 20%, that is, most of the electric power it bears is converted into heat energy. The temperature rise of the voice coil will increase the impedance of the voice coil, making it mismatched with the whole machine. Therefore, to significantly increase the power handling of the speaker, improving the heat dissipation of the voice coil is the key issue. A magnetic fluid speaker solves this problem well. The structure of the magnetic fluid speaker is almost the same as that of the traditional electric speaker. The main difference is that the magnetic fluid speaker adds a certain amount of magnetic liquid to the magnetic gap. Since the magnetic induction intensity in the magnetic gap is very strong, the magnetic liquid can be stably adsorbed in the magnetic gap even when the voice coil vibrates. The magnetic liquid is a glue containing fine iron powder with an average diameter of 0.001 microns. These iron powders are suspended in the glue. In order to prevent the iron powders from sticking to each other, people also cover the surface of the iron particles with a very thin polymer film.
Since the voice coil is always in the liquid when working, the heat generated by the voice coil is directly transferred to the glue, and then to the magnetic circuit system by the liquid to dissipate. Therefore, the heat dissipation of the magnetic fluid speaker has been significantly improved, and its rated power has been greatly increased. The presence of magnetic fluid also enhances the damping performance of the speaker, thereby effectively reducing the height of the resonance peak on the frequency characteristic curve, making its characteristic curve smoother.