Speaker sound way

The basic principle of moving coils comes from Fleming's left-hand rule. A current-carrying wire is placed perpendicular to the magnetic field lines between the north and south poles of the magnet. The wire is moved by the interaction of magnetic lines and currents to attach a diaphragm. In this line, the diaphragm moves forward and backward as the current changes. At present, more than 90 percent of the cones are dynamically designed.

Electromagnetic type in the middle of a U-shaped magnet is installed in the middle of the movable yoke piece (armature), when the current flows through the coil, the armature will be subject to magnetization and magnet repulsion phenomenon, and at the same time drive the diaphragm movement. This kind of design is cheap but not effective, so it is mostly used in telephone sets and small earphones.

Inductive and electromagnetic principles are similar, but the armature is doubled, and the two voice coils on the magnet are not symmetrical. When the signal current passes through, the two armature move to push each other for different magnetic fluxes. The difference with electromagnetic is that the inductor can regenerate lower frequency, but the efficiency is very low.

The basic principle of electrostatic type is Coulomb's law, which is usually vacuum vaporized with a plastic film and inductive materials such as aluminum. Two diaphragms are placed face to face. When one of them is filled with positive current, the other is A small current is induced, and the sound can be generated by pushing air with each other's attraction and repulsion. Because of its light weight and small vibration dispersion, the electrostatic monomer is easy to get clear and transparent mid- and high-pitched sound. It has low power to the bass and its efficiency is not high. It is easy to collect dust by using the DC power source. At present, manufacturers such as Martin-Logan have successfully developed electrostatic and dynamic hybrid horns to solve the problem of lack of electrostatic bass, and the use of electrostatic type in headphones is also very extensive.

The flat type was first developed by Japan's SONY. The design of the voice coil is still the theme of moving coils. However, the planar diaphragm of the honeycomb structure has been replaced by a honeycomb diaphragm because of the small number of voids and the characteristics are better, but the efficiency is also improved. Low.

The ribbon type has no traditional voice coil design. The diaphragm is made of a very thin metal and the current flows directly into the body of the track to make it vibrate. Because its diaphragm is a voice coil, it is very lightweight, has excellent transient response, and high frequency response. However, the efficiency and low impedance of ribbon-type speakers have been a big challenge for the expansion of the machine, Apogee can be represented. Another way is to have a voice coil, but the voice coil is directly printed on the plastic sheet, which can solve part of the low-impedance problem, Magpang this design leader.

The horn type diaphragm pushes the air at the bottom of the horn and works because the sound is not diffused so it is very efficient. However, since the shape and length of the horn will affect the timbre, it is not easy to replay low frequencies. Now it is mostly used in giant PAs. On the system or high pitch unit, American Klipsch is an old manufacturer of horn loudspeakers.

Among other things, the ribbon-like modified design developed by Dr. Haier in 1973, known as the Haier horn, is theoretically excellent, but Taiwanese users are rare. The piezoelectric type uses a piezoelectric material such as titanic acid, plus a voltage to make it stretch or contract and sound design. Pioneer used a high polymer to improve the piezoelectric design for use on their tweeters. Ionic ionic (Ion) is the use of high-pressure discharge to make the air become charged quality. After the AC voltage is applied, these free charged molecules will sound because of vibration. At present, they can only be used in high-frequency monomers. Philips also developed an active feedback loudspeaker (MFB) with an active feedback circuit inside the loudspeaker to reduce distortion.