7.The five most direct factors that determine the sound quality of Bluetooth headsets

1. Bluetooth version

4.2 and below 4.0 Bluetooth transmission rate is not very high, there will be problems such as interference, disconnection, etc. After 5.0, this problem has been solved well, and now most of them have begun to use 5.0 above version.

2. Encoding format

Bluetooth audio transmission protocol, the transmission efficiency of different protocols will also be different, which will affect the sound quality to some extent. In fact, all encodings will have a certain loss of sound quality, but some are more and some are less.

At present, the more common encodings are Aptx, AAC, and SBC.

3. Sound unit

Speaker cavity design and sound unit size. The sound cavity is an echo field. If the structure of the plastic shell mold is unreasonable, the sound quality performance will be poor. Theoretically speaking, the bigger the sounding unit, the better. The common sounding units on the market are 6mm, 8mm and 10mm, and there are special sizes customized for different structures.

The other is the sound of the moving iron. The sensitivity of the moving iron is higher than that of the moving coil, because the structure of the moving iron unit is almost a closed container structure, which can be driven by a little current. Due to their high sensitivity, moving-iron headphones are superior to moving-iron headphones in terms of dynamic performance, instantaneous detail performance and sound density. Cool tone, high resolution! The low-frequency volume performance is weaker than that of the dynamic coil of the same level. Due to the special structure of the moving iron unit, the direction of the sound pattern is basically determined.

4. Diaphragm material

The material of the diaphragm is also a very important part in determining the sound quality. There are various materials. The diaphragm of the earphone is divided into: pulp, polymer, composite, and metal. The diaphragms of mid-to-high-end earphone products often use composite diaphragms , that is, the so-called "bio-composite diaphragm", "titanium metal diaphragm" and "carbon nanotube diaphragm", this diaphragm will be designed and built with 1-2 kinds of materials, such as the part of the diaphragm edge responsible for low frequency The PET material will be used, and the metal diaphragm will perform better on high frequency transients and details.

5. Tuning

Tuning is the most experienced and lengthy step in the development of the entire headset. This requires continuous adjustment by an experienced tuner to achieve the desired output effect. Different tuners have their own preferences and different tuning styles. For example, the tuning style of Deep Sea Purcell is that the three frequencies are relatively balanced, the sound is original and rough, and the details are relatively complete. BOSE's sound quality is relatively pure, Sony's tuning is more metallic, and so on.