What are the speakers?

The speaker is commonly known as the Horn, should be familiar but of devices, it is radio, tape recorder, audio equipment of important components. Common speakers have moving coil, Reed type, piezoelectric, etc. several, but the most common is the loudspeaker (also known as electric). The loudspeaker is divided into inner and outer magnet magnet, because external magnet cheap, usually more external magnet. When audio current through the coil, coil produces with audio magnetic current changes, in the permanent magnet magnetic field and attract sometimes exclusive, driving the vibration sound cone. Speakers in the circuit diagram symbol for a image in. Stereo speakers with high power, high-fidelity most requirements. For the perfect reproduction of sound, speakers and is divided into specific bass, treble, Alto, to carry out their duties. Bass speaker cone no longer constitutes a single material, fabric, nylon side and rubber edges, and other speakers, the paper Bowl more flexible, more rich bass. # Drum speaker, ball treble speakers make treble clarity. There is also a full-frequency speaker, it will be high and bass speakers together. Speakers generally marked with a nominal power and nominal impedance values, for example, 0.25 W, 8 Ω. General considers the speaker diameter, the nominal power is also large. When used, the input power is best not to exceed the nominal power is too much and prevent damage. Multimeter R1 resistance stalls test the speakers, if it has issued instructions to cackle basically be used. Measure of the resistance value is direct current resistance, higher than nominal impedance values, is normal. There is also a Piezoelectric ceramic plate, is also a vocal element that uses the piezoelectric effect, can be made audible components and can do receive sound components. And it is cheap, the vocal element on a birthday card is it. Piezoelectric ceramic plate is in the Park-shaped copper base plate coated with a layer thickness of about 1 mm piezoelectric ceramics, ceramic surface deposits a layer of silver coating layer, the silver coating layer and copper backplane is its two electrodes. Piezoelectric ceramics have a wonderful characteristics-piezoelectric effect: if it bends, its surface will appear different, such as reverse bending of electric charge, charge of polarity will instead. Wonderful is if the Piezoelectric ceramic plate of two electrodes to impose a certain voltage, it will be bent, when voltage direction changes, bending direction also changed. Utilizing piezoelectric effect, there is a kind of acoustic-electrical, mechanical and electrical transforming of dual-use devices, can be used when the microphone: address by of the Piezoelectric ceramic plate, so that it is affected by Sonic vibrations that occur before and after the bend, and, of course, the human eye can't tell this bending, Piezoelectric ceramic plate of two electrodes will have audio voltage output. On the contrary, to be sure the voltage of the audio added to the Piezoelectric ceramic plate of the Poles, because audio voltage polarity and size changing, Piezoelectric ceramic chip will produce the appropriate bending movement, promote the formation of sounds, this air, it also became the trumpet. Piezoelectric ceramic plate as a kind of electronic components, in a new buying comes, is without a leader, needs its own welding. Generally use multiple soft line, first peeling tin lined, welding head is fast, small, easy to spot bad on Piezoelectric ceramic pieces of delicate silver plating layer. There is also a small in BP machine, alarm clock, widely used in hearing xiangqi essentially is the electromagnetic type.