When you buy speakers or headphones, you will inevitably be affected by the subjective analysis of others, such as it sounds good and the sound is thick...
In fact, the sound quality index is based on objective standard measurement and evaluation. The study found that the sound quality of the speaker depends on the three indexes of the diaphragm material: material elasticity (E), density (ρ) and appropriate internal damping, so it is adopted What kind of diaphragm material generally determines the sound quality of the speaker.
We usually say that the sound quality of speakers is good, but in fact it means that the internal damping is large and the E/ρ (the quotient of material elasticity and density) is large. It is very difficult to satisfy both E/ρ and internal damping at the same time. For example, the rigid alloy diaphragm has high elasticity, low density, and E/ρ is relatively large, but the damping of metal is small, and the sound is difficult to stop quickly. It is not very clean; on the contrary, the damping of the pulp material diaphragm is large, the sound is soft, the sound rises (sound from scratch) is relatively slow, the fall speed is relatively fast, and the strength is not enough.
The performance of the speaker's diaphragm can be measured by the speaker's ability to respond to the input signal and its ability to discern the frequency response. The smaller the frequency response value, the flatter the speaker's frequency response curve, the smaller the distortion, and the better the performance. Under normal circumstances, the frequency response range of a good speaker should be 20Hz to 20000Hz. When a 20Hz-20000Hz audio signal enters this speaker, the output music will have enough low frequency dive and excellent high frequency performance. . Signal speakers above and below this frequency response range cannot be processed. For example, if the audio signal of 5Hz-25000Hz enters this speaker, we will feel that the music is very narrow and lacks expressiveness.
Since the diaphragm is so important to the sound quality of the speaker, what material is used for the diaphragm? Take the woofer diaphragm we usually use, there are aluminum alloy diaphragm, aluminum-magnesium alloy diaphragm, ceramic diaphragm, carbon fiber diaphragm, bulletproof cloth diaphragm, glass fiber diaphragm, acrylic diaphragm, paper diaphragm, etc. , Its structure is mainly cone type, and a small amount of flat type. Today we mainly introduce four kinds.
Paper cone-inject the pulp stream into the designed basin-shaped net mold, when the pulp is deposited to a certain thickness, it is copied out, dried and then processed to form a paper cone diaphragm. Because the paper cone contains a lot of fiber, the audio is easily absorbed during transmission and has good damping. In terms of sense of hearing, the paper cone sounds natural and full of bass. The disadvantage is that the moisture resistance is poor, the density becomes higher and the rigidity becomes worse after absorbing moisture, especially the paper cone material will fatigue after a long period of dry and wet cycles; secondly, it is difficult to control the consistency during manufacturing.
Wool woven cone——The vibrating membrane of soft wool fiber is penetrated into the pulp of the paper cone of the woofer. The advantage is that it performs very well for soft music and light music, and the vocals are mellow and natural. But the bass effect is mediocre, lacking power and shock, and the performance of rock music and marches is not satisfactory.
Bulletproof cloth basin-bulletproof cloth usually also has a rubber edge or foam edge, which will make the bass effect of the speaker better, the frequency response is wider, the sound is more three-dimensional, and it can withstand greater power, so bulletproof Cloth basin is suitable for big dynamic music, it is a good choice for game fans and those who like strong bass, but it does not perform well in playing light music, and the manufacturing process is complicated and the cost is high.
PP (polypropylene) basin-refers to the cone basin formed by plastic injection molding or other methods. Its damping characteristics are very good, and the audio signal will be quickly absorbed and consumed when it is transmitted. In the sense of hearing, the distortion is low, and the performance is remarkable in all aspects. It is widely used in high-quality speakers, but it has insufficient rigidity and large quality.
After reading this article, you will be more targeted when buying speakers, rather than just relying on intuitive feelings to judge.