The speaker market is a mixed bag, and the price ranges from tens of yuan to thousands of yuan. How to choose a suitable speaker according to my needs has become a problem that plagues many people. What kind of speakers are really good speakers? Especially the "noob" friends who don’t know much about speakers can only look at the appearance and listen to a short piece of deafening music played by the business, and can only feel it with the senses; from the perspective of technical goals, they don’t know where to go. Judge the pros and cons of speakers by hand. This article is complicated to introduce the technical goals of speakers. I hope these contents can provide you with some references when purchasing speakers.
Speaker technical indicators: sound technology
Nowadays, hardware 3D sound effect technology is relatively rare, including SRS, APX, Q-SOUND and Virtaul Dolby. Although they have different ways of completing them, they can all make people feel distinct three-dimensional effects. Among them, the first one is The most rare. They all use Extended STereo, which is the additional processing of the sound signal through the circuit, so that the listener feels that the sound direction is extended to the outside of the two speakers, so as to stop the sound expansion and give people a sense of space. And the sense of plane, produce a more open plane sound effect. In addition, there are two sound enhancement technologies: active electromechanical servo technology and BBE high-definition plateau sound reproduction system technology, which also have a certain effect on improving sound quality.
Speaker technical indicators: frequency response range
The full name of the frequency response range is called frequency range and frequency echo. The former refers to the range between the lowest invalid playback frequency and the highest invalid playback frequency of the speaker system; the latter refers to the sound pressure generated by the speaker when a constant voltage input audio signal is connected to the system. The scene of increasing or attenuating, and the phase changing with frequency. This correlation between sound pressure and phase and frequency is called frequency response, in decibels (dB). The difference of the curve of sound pressure and phase lag with frequency is called "amplitude-frequency characteristic" and "phase-frequency characteristic", collectively referred to as "frequency characteristic". This is an important goal to examine the function of speakers. It has an indirect relationship with the function and price of the speakers. The smaller the decibel value, the flatter the speaker's frequency response curve, the smaller the distortion, and the higher the function. For example, the frequency response of a speaker is 60Hz~18kHz+/-3dB. These two concepts are sometimes indistinguishable and are called frequency response. From a practical point of view, the harmonic components that make up the sound are very complicated. It is not that the wider the frequency range makes the sound unpleasant, but this is fundamentally correct for mid-to-high-end multimedia speakers. Nowadays, speaker manufacturers generally mark the range of system frequency response too large, and the high-frequency local difference is not too much, but the mark on the high-end end is extremely unreal, so I remind everyone that the low-frequency sound must be heard, not casually Confidence the value on the leaflet.
Speaker technical indicators: sensitivity
The target refers to the sound pressure level measured at the center one meter behind the stereo vertical center axis of the speaker when outputting a 1W/1kHz signal to the speaker output terminal. The unit of sensitivity is decibel (dB). For every 3dB difference in the sensitivity of the speakers, the input sound pressure will be doubled. The sensitivity of ordinary speakers is in the range of 85-90dB. Below 85dB is low sensitivity, and above 90dB is high sensitivity. Generally, the sensitivity of multimedia speakers is slightly lower.
Speaker technical indicators: power
The power indicator of the speakers is very confusing. To put it more complexly, power refers to how powerful the sound of the speaker can be. According to international standards, there are two ways to label power: additional power and maximum received power (instant power or peak power PMPO). The additional power refers to the maximum undistorted power that the speaker can recover by giving the speaker a continuous analog signal with a regular waveform in the additional frequency range, and the maximum received power is the maximum electrical power that the speaker does not cause any damage. Generally, in order to fit the minds of consumers, businesses usually set a large standard for music power, so when buying multimedia speakers, they should take the extra power as the standard. The maximum received power of the speaker is mainly determined by the chip power of the power reducer, and also has a lot to do with the power transformer. You can roughly know the component of the transformer by taking a look at the component difference between the main and sub speakers, and the heavier the weight, the greater the power. However, the power of the speaker is not the bigger the better, and the application is the best. For an ordinary household user's room of about 20 square meters, the real power of 50W is enough, and there is no need to go overboard and pursue high power.
Speaker technical indicators: distortion
The definition of the distortion of the speaker is fundamentally opposite to the distortion of the reducer. The difference is that the output of the reducer is an electric signal, and the input is still an electric signal, while the speaker outputs an electric signal and the input is a sound wave signal. Therefore, the distortion of the speaker refers to the distortion of the electro-acoustic signal conversion. The allowable range of sound wave distortion is within 10%, and ordinary human ears are not sensitive to distortion within 5%. It is best not to buy speakers with a distortion greater than 5%.
Speaker technical indicators: signal-to-noise ratio
The target refers to the ratio of the normal sound signal to the noise signal played back by the speaker. The signal-to-noise ratio is low, and the sound is serious when small signals are output. The sound in the entire range becomes turbid and unclear. I don't know what sound is being sent, which seriously affects the sound quality. Speakers with a signal-to-noise ratio below 80dB (including tweeters below 60dB) are recommended not to be purchased.
Speaker technical indicators: impedance
The target refers to the ratio of the voltage to the current of the output signal. The output impedance of a speaker is generally divided into two types: high impedance and low impedance. Generally, the output impedance is higher than 16 ohms, and the impedance lower than 8 ohms is low impedance. The standard impedance of the speakers is 8 ohms. The nominal impedance of speakers on the market is 4 ohms, 5 ohms, 6 ohms, 8 ohms, 16 ohms, etc. Although this goal is related to the function of the speakers, it is best not to buy low-impedance speakers. The recommended value is the norm. This is because low-impedance speakers can obtain larger input power when the power amplifier is opposite to the input power. However, if the impedance is too low, it will cause underdamping and treble degradation.