For audio power amplifier, how can we judge its advantages and disadvantages? Today, Jazz Dragon Sound engineers give you some suggestions, so that when you face such problems, you will no longer have headaches and worries.

1、 Many people believe that power amplifiers are "the heavier the better". Most low-quality power amplifiers use ring transformers, and many use dual ring cows with fever. However, the silicon steel sheet of this kind of ring cow is of poor quality, and the winding process is not up to standard. As a result, the efficiency is low and the actual power is small, especially when it is quiet, it is easy to hear the ring cow "humming".

2、 The domestic capacitors with large size and small capacity are used to charge the imported famous brand capacitors. Some manufacturers even use the overstocked early capacitors to update the packaging and install new capacitors. The actual withstand voltage and capacity of these capacitors can not reach the standard value at all. These capacitors are generally lighter than the real ones.

3、 It can withstand 4558 or 082 charging 5532 and other medium and high grade power amplifiers. Sometimes it is found that many so-called 5532 are actually polished from 4558. There are also the most counterfeit domestic power amplifier tubes filled with imported tubes, especially Toshiba tubes.

4、 It is a low-quality power amplifier that often has 5-channel or even 7-channel output. But in fact, the surround and center channels of many power amplifiers are connected by the resistance of the left and right main channels in series. Although some power amplifiers are equipped with independent amplification circuits, they only undergo simple delay processing, and there is no dedicated decoding circuit or sound field processing circuit at all. When identifying this type of power amplifier, if it is found that the surround and center channels cannot adjust the volume separately, it must be a false surround caused by the main channel series resistance.

If the nominal Dolby directional logic decoding function is available but the noise test is not available, or the surround speaker also sounds when only mono signal is input, the power amplifier belongs to the pseudo surround sound power amplifier. For power amplifiers using SRS, Q-Sound and other technologies, their authenticity can also be identified by comparing the opening and closing of surround functions and selecting different surround modes. It is also necessary to remind you that some audio manufacturers have actually adopted Dolby decoding chips such as M69032, but they have not passed Dolby certification and also affixed Dolby logo. Such amplifier can not guarantee the necessary channel separation and other performance marks, and it is also a fake.

5、 It is lack of complete protection functions. Although low-quality machines have startup impact protection functions, most of them omit the necessary over-current, over-voltage and output DC protection functions, resulting in poor reliability of the whole machine. Once problems occur, expensive horn units may be burned. For the identification of such counterfeiting methods, first, check the circuit diagram to determine whether the design has perfect protection function; The other is short circuit output terminal, if the power amplifier does not have protection action. It is likely that these protective circuits are omitted, or at least poorly adjusted.

6、 Class B is regarded as Class A, and one-sided pursuit of multi-function and appearance neglects the circuit design level, which is used as a selling point to boast. This is all "advanced" fraud. For these "distinctive" amplifiers, if consumers are not familiar with audio equipment, it is better to ask knowledgeable people to help select them, and try to choose products from large audio manufacturers that are more reliable.