The initial understanding of the plug-in card speaker can be identified by the steps of "viewing, listening and recognizing" : the first view of the process and parameters, the second listen to the sound quality, the third recognize the brand.

First view technology and parameters

First view of the process is to judge the quality of the sound box from the appearance of the first image, whether the production process is accurate in place, fake and shoddy products generally do not pay attention to these details, so a little effort can be correctly judged. The technical parameters of a plug-in card sound box are nothing more than frequency range, output power, signal-to-noise ratio.

The frequency range is generally 90Hz~20KHz. 90Hz indicates the extension value of the plug-in speaker in the low frequency direction. The lower the number, the better the low-frequency response of the plug-in speaker.

The output power is a reference index of the card speaker, expressed in how many watts, this index can not indicate the quality of the speaker, only indicates that to promote the power amplifier required by the card speaker, the battery needs to have the required output power.

Signal-to-noise ratio refers to the voltage of the output signal of the amplifier and the noise voltage output at the same time, often expressed in the number of decibels, the higher the signal-to-noise ratio of the device indicates that it produces less noise. Generally speaking, the higher the SNR, the lower the noise mixed into the signal and the higher the quality of the sound played back. Otherwise, the opposite is true. Generally, the signal-to-noise ratio should not be lower than 70dB. The signal-to-noise ratio of a hi-fi speaker should be higher than 110dB. The minimum signal-to-noise ratio marked by a card-in speaker is usually between 70dB and 90dB.

Sound quality

Card speakers are mostly made of plastic material, the smaller the material density of the speaker shell, the greater the vibration generated by the box when the sound is emitted. From this aspect, it is difficult to achieve ultra-low tone effect in card speakers to some extent, which is almost a common problem of all card speakers. But the so-called extreme, although the card speaker in the bass is slightly insufficient, high and medium frequency performance can do very well. Different design structure, different cavity size, the sound quality of the card speakers may still be very different.

Three recognition brand

Good plug-in card speakers are well-made gold-plated or chromium-plated brand marks, if the trademark is not registered mark, there is no anti-counterfeiting certification mark on the outer packaging, there is no warranty card inside the packaging, most of these three products are counterfeit and shoddy.