Don't confuse volume and power when buying audio

When buying an audio, when you ask to compare the power of two different machines, the seller will open the volume potentiometers of the two machines to a certain position, such as the position in the center, people are used to the clock position of the clock. In comparison, it is called to open to 12 o'clock, and then listen to who's loud volume, it is judged who's power is large. In fact, this is completely misleading, because this comparison method will often get the opposite result of the actual, and will even be used by unscrupulous merchants or manufacturers to let you fall into the trap. So what is wrong with this method of judgment?

On this issue, you may be misled by two illusions. First, the illusion caused by the gain of the machine. Second, the illusion caused by the characteristics of the potentiometer. The following is a description of the potentiometer's problems.

The potentiometer is a component that changes the strength of the signal. The process of rotating the potentiometer actually changes the attenuation coefficient. The minimum position is 0 and the maximum position is 1. However, the attenuation coefficient corresponding to a position in the rotation process is not the same for each potentiometer. For example, when the position is rotated to half, the attenuation coefficient is not 0.5. If the half attenuation coefficient is half, and the rotation 1/4 attenuation coefficient is 1/4, this potentiometer is called a linear potentiometer. But people have long discovered that the human ear's feeling of volume is not linear. Attenuating the signal by half does not sound like it is half-small. In order to make this attenuation process conform to the characteristics of human hearing, then A potentiometer called an exponential characteristic appears. The exponential characteristic is characterized by a slow and fast decay characteristic, but because it offsets the nonlinearity of the human ear, it makes the sense of hearing uniform. So in the classic circuit design theory, the volume potentiometer uses exponential characteristics. If you use a linear potentiometer to make a volume potentiometer, it will feel great when the volume is turned on a little. In the dead of night, you can't get a small volume, making it hard to control the volume. This is because the machine reaches the maximum power that can be output too quickly. In fact, increasing the power output of the machine is limited and even distorted. Welcome to China Home Theater Decoration Network

As for the exponential potentiometer described above, the potentiometer is compared with the linear potentiometer described above, and the volume is small at the same position, but there is no need to worry about the loss of the maximum output power.

The exponential potentiometer expands the useful adjustment range, and the range of power-to-head phenomena or the resulting distortion can be minimized. Therefore, according to the formal design concept, if you use a linear potentiometer to make volume adjustments, it will be considered as an error or ignorance. However, in order to make the machine feel more powerful, people say it directly, just to be savvy, in order to win in the competition mentioned earlier in this article, some manufacturers still do so.

Water Purifier

Automatic Water Purifier,Electric Water Purifier,Low Cost Water Purifier,Household Water Purifier

JOYOUNG COMPANY LIMITED , https://www.globaljoyoung.com