30 to 50 dollars or so, the collection of scrap collected over is not utilized, but sold to the steel mill from the new smelting into steel, so the collection of things are all according to the catty weighing. Black or brown is a ferrite magnet, this has no value no one recycling, if it is white, is a neodymium iron boron magnet, recycling price of about 70-80 yuan / kg.
Changing electric current into the stereo, the magnet becomes an electromagnet. The direction of the current is constantly changing, the electromagnet due to the "energized wire in the magnetic field force movement" and also non-stop back and forth movement, driving the paper pot also back and forth vibration. The sound will have sound.
Audio is a simplified everyday word, is the short form of audio system. That is, it stands for a complete set of equipment that can restore playback of audio signals.
With the progress of society, people aspire to a more colorful life. Song and dance as a form of entertainment handed down for thousands of years, deep into the lives of people of all races. But with the development and progress of science and technology, people for song and dance performance form and venue requirements more and more, more and more high. Sound system with people's needs continue to improve and perfect. Large enough to meet the needs of tens of thousands of people concerts live sound reinforcement, small enough to meet the needs of individual families playing musical instruments, K song.