What is the difference between digital amplifier and analog amplifier

With the advancement of technology and the continuous maturity of power amplifier technology, digital power amplifier chips have been widely used in home theater and TV or monitor TV, mooring multimedia room speakers, projectors and other products, so digital power amplifier and analog power amplifier -Two types of power amplifiers are often compared, which one is better? What are the differences, what are the advantages of each, and why are digital power amplifiers slowly replacing traditional analog power amplifiers?

In fact, for power amplifiers, the final judgment standard is still the quality of sound quality. So how do you start? Let me introduce the difference between digital power amplifier and analog power amplifier.

First of all, before understanding the difference between digital power amplifier and analog power amplifier, you must first know what is digital power amplifier and what is analog power amplifier?

A digital power amplifier is an amplifier with low distortion, low noise, and a large dynamic range, and an analog power amplifier is a device that takes a low-power analog signal as input and outputs a more powerful version of the same signal.

The well-known audio power amplifiers include Class A amplifiers, Class B amplifiers, Class A and B amplifiers, and Class D amplifiers. In terms of signal form, the first three types of amplifiers deal with all It is an analog signal, which is an analog audio power amplifier, that is, an analog power amplifier. The latter is a digital audio power amplifier that processes digital signals, that is, a digital power amplifier.

In the first decade of the 21st century, although the underlying technology can be traced back to the 1950s. More precisely, Class D amplifiers, these circuits, unlike pure analog amplifiers, are capable of taking a purely digital signal and amplifying it, producing an analog speaker-level output. On the other hand, with an analog-to-digital converter, they can also take the analog signal and amplify it. The main advantage of digital amplifiers over analog amplifiers is higher power, allowing cheaper digital circuits to generate as much amplification as finer and more expensive class AB analog amplifiers.

The difference between digital power amplifier and analog power amplifier is not noticed by most people.

1. Digital power amplifier is divided into power mode digital power amplifier and sound quality mode digital power amplifier. The digital power amplifier in power mode is linear and uses digital signal amplification to make the output signal and the input signal phase exactly the same. During the transmission process of the digital signal, the sound is closer to the real (high fidelity) and close to the human ear. The sound quality mode is a custom circuit, suitable for 4/4 surround speakers are used, of course, there are also analog power amplifiers that reduce the use of low-power playback devices such as 13-43 watts, so I won't go into details here.

2. The digital power amplifier has a large modulus. For tuning, you generally need to make sure that the power of the signal is about 150 watts, which is relatively smooth, while the volume of the ordinary analog output of more than 200 watts is enough. When it is too large or too small, There will be obvious noise or overload phenomenon.

3. The digital power amplifier is small in size/light in weight, lower in cost and higher in power. The digital power amplifier generally uses a switching power supply for power supply, and the analog power amplifier uses a transformer. The advantages of digital power amplifier are high efficiency and low heat dissipation requirements, simple peripheral circuits and low cost. The advantages of analog power amplifiers are better sound than digital power amplifiers, but the disadvantages are high cost, high heat dissipation requirements, heavy weight, complex circuit structure and high maintenance difficulty.

4. The place where the digital power amplifier channel is converted is similar to the audio interface. You need to determine the sampling rate of your input signal, such as about 24bit. The analog power amplifier input is 20bit signal. The digital power amplifier may not output 24bit signal through encoding. This needs to be adjusted by yourself. . To sum up, the advantage of digital power amplifier is to adjust the volume by yourself, but the advantage is that the noise is not easy to deal with, and it sounds smoother. The advantage of analog power amplifiers is that the noise is easy to handle and sounds messy.

Power amplifier matching needs to take into account the power of all signals, and selecting the right one can make the sound better. The matching of sampling rate, code rate and channel is also critical to signal noise. Regarding debugging, the digital power amplifier can directly adjust the volume with the power amplifier line control board. The way is fine. Because the ordinary power amplifier obtains the data of another device through the signal, it also needs to be adjusted according to the sampling rate of the power amplifier line control board, so it needs a lot of learning for debugging.