The selection of speakers generally starts from the shape. If a multimedia active speaker has a smooth and smooth appearance and a fine and even color, it will first give people a heart-warming feeling. Then on this basis, carefully check whether the joint of the speaker box is even and tight, and whether the shape, adjustment knob, function key and jack position are reasonably distributed (note: if the subwoofer is to be configured, the speaker must provide a signal expansion statement for the insertion of the subwoofer). In any case, you can't let go of any nuance when observing, including the marks or patterns on the speaker. Exquisite, correct and clear, which shows that this speaker has excellent workmanship and first-class quality. If you are not at ease, you can open the speaker with the consent of the seller to see if the internal parts and wiring are concise and reasonable. Check whether the box feels smooth and flat. Knocking on the box is loud, indicating that it is durable and the sound distortion is small. Try to rotate and plug in the knob, switch and jack, and you should feel the resistance is small and natural and smooth.
2. Estimate the maximum output power of the speaker.
If you choose a pair of speakers in terms of technology and appearance, you can pick them up and see how heavy they are, so as to estimate the maximum output power of the speakers. Generally speaking, the undistorted power of a speaker should be at least 20W+20W, that is, 20W for each channel. At present, the maximum output power of multimedia active speakers in the market is PMPO music power, which is purely an indicator of advertising effect, but in fact, it should be noted that the maximum undistorted power is only 1/8 of the PMPO power value. For example, a speaker with power of 160W may actually have undistorted power of less than 20W. Since more than 95% of multimedia active speakers are still powered by AC transformers, we can estimate the actual maximum output power of speakers according to the weights of transformers and amplification boards in the box. Generally speaking, the weight of 25W transformer is about 1 kg, and that of 75W transformer is about 2 kg. So we only need to estimate the maximum output power of this multimedia active speaker according to the weight difference between the two speakers.
3. Check the magnetic shielding effect of the speaker.
Because the color display is the most sensitive to the interference of the surrounding magnetic field, as long as it is close to the display, the magnetic shielding effect of the speaker can be found out. If the image is distorted when the speaker is close to the display, it means that the magnetic shielding effect of the speaker is not good.
4. Feel the sealing performance of the speaker.
At present, most multimedia active speakers use phase inversion, and there is a hole on the speaker, which is called phase inversion port. The better the sealing of the sound box, the better the sound effect. To check this indicator, you can put your hand near the inverter when the speaker is working. When the sound is drums or explosions, there should be obvious air rushing out or inhaling in the frequency converter. Like the wind, the more obvious the feeling, the better the sealing performance of the speaker. The tightness of the loudspeaker box directly affects the low frequency response index of the loudspeaker box.
5. Check static noise
When choosing multimedia active speakers, we should make full use of our ears to judge the quality and effect of the sound reproduced by the speakers. First, listen to the static noise of the speaker. When the ideal speaker is working, if there is no signal, even if the volume is adjusted to the maximum, you should not hear the sound. So we can connect the speaker to the power supply instead of the signal line, and then turn the volume to the maximum position. At this time, if we can't hear or only hear a slight rustle, then the static index of this speaker is qualified. Secondly, listen to the sound quality and identify the frequency response of the speaker. Theoretically, people's ears can hear sounds with a frequency between 20 Hz and 20 kHz. In fact, all kinds of sounds in nature are not single-frequency sounds, but "polyphony" of a fundamental frequency plus various sounds several times the fundamental frequency. The expression of sound frequency is tone. For example, women's voices are higher than men's, which is what we usually call sharp or thin. The sounds of people and animals in nature, the sounds of rain and thunder, and the sounds made by various man-made objects such as cars and planes are not single-frequency sounds, but the frequency range of these sounds is basically within 15Hz~20KHz. Therefore, when the speaker restores these sounds, it needs to reflect the fundamental frequency and harmonic frequency of all kinds of sounds truthfully, otherwise the reproduced sound will be unreal and unnatural. For example, if we see a person riding a horse on the stone road in the mountains on the screen, then the sound of hooves played back by the speaker is wrapped like horseshoes, indicating that the reproduction ability of the speaker in the middle and high frequencies is not enough; If you see a big drum playing on the screen, but the sound you hear is like playing a waist drum, it is that the bass reduction ability of the speaker is not enough. So when we buy speakers, we can play a familiar song or movie plot on CD or VCD. If it sounds normal, there is no feeling of turbidity or astringency. China HIFI home cinema network
6. Check the maximum undistorted power
After connecting the signal input line of the speaker with the LineOut of the sound card (or MPEG player card) of the computer, choose a CD or VCD that is familiar with the songs, and adjust the volume to the maximum undistorted power, which is the maximum undistorted power of the speaker, if you think the volume is enough. Finally, if you are financially strong, you might as well buy wooden speakers. Because different materials have different effects on sound, wooden speakers can ensure better clarity and less distortion.
7. Consider the matching of sound combinations
Buying a stereo is different from buying other things. This stereo has its own personality. If it is not well matched, it will be as embarrassing as a couple's "personality disagreement". For example, most of the power amplifiers in Japan have a hard sound base and heavy digital flavor, and are only suitable for matching with soft and warm speakers. With the same "cold" German speakers and the recognized "hard" JBL, the sound will be unbearable or even ugly. However, many merchants, including some agents of brand-name equipment, ignore this factor in order to promote their products, and often engage in some "incompatible" collocation, which is very irresponsible. In addition to requiring businesses to be self-disciplined, consumers should also learn collocation knowledge to avoid blindly listening to advertising recommendations. In addition, the same price, due to different brands, its music quality is also different, and it often happens that the products purchased at high prices are not as good as those purchased at low prices. Therefore, understanding the knowledge of listening is a necessary condition for purchasing audio.