What are the factors that affect the sound？

1. The maximum output power of the cheap bluetooth speakers.

Music generally has a large dynamic range, and the instantaneous power may exceed 10 times the average power. The mainstream audio systems now use transistors or integrated circuits as power amplifiers.

A common problem of this type of power amplifier is that there is a fixed saturation point. (In the electronic tube era (the 1960s), there is almost no such problem, because the electronic tube characteristic curve is relatively smooth)

Generally speaking, if the saturation point of the power amplifier is 100w, then a piece of music with an average power of 50w may output an instantaneous power of 500w. This power will actually only output 100w. The waveform diagram is as follows:

It can be seen from the figure that the low-power waveform has no distortion, while the high-power waveform is seriously distorted. Some people vividly call this distortion "topping".

Generally speaking, the power amplifier should have a certain amount of power reserve. When the 100w power amplifier is actually turned on to the maximum volume, the output should be only about 50w to ensure that the loss of sound quality is in an acceptable state.

Some people report that noise will be generated when the volume of the cheap bluetooth speaker is turned on. The saturation distortion of the power amplifier is one of the reasons for this noise. Two other common factors are: 1). The cheap bluetooth speaker itself is damaged or the wiring is poor. 2). The installation of the cheap bluetooth speaker is not firm, or the cheap bluetooth speaker itself has other parts that will vibrate.

Only profitable manufacturers often choose power amplifiers with insufficient power to reduce costs.

2. The material of the speaker itself.

A cheap bluetooth speaker with a certain thickness is easier to output good sound quality. The material of this type of cheap bluetooth speakers is generally solid wood, thick synthetic materials (such as resin, plastic, etc.), and some metal accessories may be used. Old speakers are also cast in asphalt.

Weight, this is another factor. Cheap bluetooth speakers that are too light will make noise due to vibration, and some will be moved by the vibration. Thin-shell plastic speakers are the most typical representatives.

Hardness, the front of the cheap bluetooth speaker should have enough stiffness to reduce sound attenuation.

3. Distortion of the wiring used by the cheap bluetooth speakers and other accessories. These factors require professional instruments to be effectively evaluated. For ordinary people, there is nothing that can be done. However, you can still listen to the level of hum by turning the volume to the maximum without input, which will reflect to a certain extent The pros and cons of the speaker line structure.