Moving coil. The basic principle comes from Fleming's left-handed law. If a wire with current and a magnetic line of force are vertically placed between the north and south poles of the magnet, the track line will move due to the interaction between the magnetic line of force and the current. When a diaphragm is attached to the track line, with the change of current, the diaphragm will move forward and backward. At present, more than 90% of the cone basin monomer are dynamic coil design.
　　Electromagnetic. A movable iron chopper (armature) is set up in the middle of a U-shaped magnet. When the current flows through the coil, the armature will be magnetized and the magnet will attract and repel, and drive the diaphragm to move at the same time. This kind of design is cheap but ineffective, so it is often used in the telephone barrel and small earphone.
　　Inductive. It is similar to the electromagnetic principle, but the armature is doubled, and the two voice coils on the magnet are asymmetric. When the signal current passes through, the two armatures will push each other for different magnetic flux. Unlike electromagnetism, inductance can regenerate at a lower frequency, but its efficiency is very low.
　　Electrostatic. The basic principle is Coulomb's law, which is usually treated by vacuum vaporization of plastic film and aluminum and other inductive materials. The two films are placed face to face. When one of them is applied with positive current and high voltage, the other one will induce a small current. By mutual attraction and repulsion, the air will be pushed to produce sound. Due to its light weight and small vibration dispersion, electrostatic monomer is easy to get clear and transparent mid and high pitch, which has no control over the power of low pitch. Moreover, its efficiency is not high, and it is easy to collect dust when using DC. At present, manufacturers such as Martin Logan have successfully developed electrostatic and moving coil hybrid speakers, which solve the problem of insufficient bass of electrostatic body and are widely used in earphones.
　　Flat type. The voice coil design, which was first developed by Sony in Japan, is still the theme of moving coil design. However, the cone basin diaphragm is changed into the honeycomb structure plane diaphragm, because of the few people cavity effect, the characteristics are better, but the efficiency is also low.
　　Ribbon style. Without the traditional voice coil design, the diaphragm is made of very thin metal, and the current flows directly into the channel body to make it vibrate. Because its diaphragm is voice coil, it has very light weight, excellent transient response and high frequency response. However, the efficiency and low impedance of ribbon horn have always been a great challenge to the expander, which can be represented by apogee. Another way is to have a voice coil, but the voice coil is printed directly on the plastic sheet, which can solve some of the low impedance problems. Magnepang is a leader in this kind of design.
　　Horn. The diaphragm pushes the air at the bottom of the horn to work, because the sound is not diffused during transmission, so the efficiency is very high. However, because the shape and length of the horn will affect the timbre, it is not easy to replay the low frequency. Now most of them are used in giant pa systems or treble units. Klipsch of the United States is an old horn manufacturer.
　　In addition, the ribbon type improved design developed by Dr. Haler in 1973 is called Haler horn, which is excellent in theory, but few users in Taiwan. Piezoelectricity is a design that uses piezoelectric materials such as titanic acid and voltage to make it stretch or shrink. Pioneer used high polymer to improve piezoelectricity design and used it in their treble monomer. Ion horn uses high-voltage discharge to make air become a charged mass. After applying AC voltage, these free charged molecules will make sound due to vibration. At present, it can only be used in monomers above high frequency. Philips has also developed an active feedback horn (MFB), in which an active feedback circuit is installed, which can greatly reduce the distortion.