Do you know about Active and passive audio?

                                         Do you know about  Active and passive audio?

The active sound division of the audio is also called the active frequency division. The audio signal of the host is divided in the central processing unit of the host before being amplified by the power amplifier circuit. The audio signal is divided into low-frequency signal and high-frequency signal according to the frequency response range, and then the two divided signals are input into the amplifier circuit and amplified separately. The frequency division method is digital.

Passive crossover is also called passive frequency division. The audio signal is amplified by the power amplifier circuit and then divided by the passive frequency divider, and then input to the corresponding tweeter or woofer. The principle is that the high-frequency sound is filtered out by the inductance circuit, and the remaining Low-frequency sound, and then input the low-frequency sound to the low-frequency speaker. The low-frequency sound is filtered by the electrolytic capacitor to leave the high-frequency sound, and then input to the tweeter. The frequency division method is fuzzy adjusted by the variable resistor.

The active crossover must be the main unit with active frequency division function or a digital active frequency divider installed after the audio output of the main unit. Generally, the high-end models of the Alpine main unit have the active frequency division function. It is characterized by precise frequency division points, The sound is clean after frequency.

In fact, many people have used active speakers. Those small speakers for Walkmans are active speakers, that is, a set of amplifiers are added to the general speaker box. When we want to use it, we only need the front stage and no post class. The active internal adopts the electronic sound division method, and saves the trouble of matching a suitable power amplifier; the passive speaker is an ordinary speaker, and there is only a one-frequency network inside.

The active pre-stage is the pre-stage of IC, transistor, and vacuum tube that we generally see. It has an amplification effect when the input signal is output. timbre. To put it bluntly, the passive preamplifier is the simplest. It is a volume control attenuator. Its output will be smaller than the input, but the timbre rendering is less, and usually there is only a slight difference, unlike the active preamplifier. The difference is quite large.