multimedia speakers

PC  Multimedia Speaker  sound files is how to work through the sound card , the digital audio signal into an analog audio signal and then its output port , then the audio signal level is weak , usually only a few hundred millivolts , it can not push the speaker working. And a working voltage of the speaker driver generally require a voltage of several volts , then a small signal needs to be amplified by the sound output from the amplifier ( known as amplifier ) , the amplified audio signal to the audio speaker driver can convert electrical signals into sound waves a . And now the latest multimedia speakers USB sound card may not be required , it introduces a digital audio signal output of the computer through the USB interface , and USB multimedia speakers this signal through a dedicated internal USB IC chip converts quasi audio signal in order to achieve substituted card function.