Comparison of empty paper cone speakers and inverted speakers

Car Audio Crystal 3.2*2.5mm 3225 24M (24.000MHZ) 20PF 10PPM 20PPM 30PPM

Probe domestic double-head probe 038-BB-5.7L The shape of the two ends of the needle is outside the pointed needle

Photocoupler

The basic principle of the empty cone speaker is to use the resonance of the mass of the air spring and the vibration system (mainly the paper cone) inside the box, that is, the vibration by the active speaker. The air cone is re-energized by the air to make it vibrate accordingly. From this point of view, it is similar to the resonance principle formed by the air quality of the acoustic guide and the air sound in the speaker, and is very similar to the inverted speaker system, but compared with the inverted speaker. It has many advantages.

In the inverted speaker, the air spring formed by the air inside the speaker and the air quality inside the guide constitute a resonance, and the empty cone speaker uses the air spring in the box and the support member of the empty paper cone to form a complex sound and air. The resonance of the cone mass together is similar to that shown in Figure 1. A scale is placed on one end of the spring, and one end of the spring is shaken by hand. If the frequency of the vibration is gradually increased from low, then the hand and the scale move together at the beginning, and soon the scale and the spring form a resonance, and the scale is swayed into a large vibration state. At the same time, because the scale absorbs vibration energy, the vibration amplitude of the upper end of the spring is very small. When we shake hands, we do not need to add a large driving force to maintain the vibration. If the vibration frequency is further increased, the vibration speed of the scale is slowed due to the inertia, and the vibration is stopped shortly.

On the lowest frequency band of the above vibration. The movement of the hand and the scale, ie the speaker and the empty cone (or the air inside the duct), is completely inverted from the outside of the box and therefore does not produce an effective amount of acoustic radiation. In the vicinity of the resonance point fP, the speaker vibration is almost stopped, and no sound is radiated. At this time, the energy for preventing the radiation of the guide or the empty paper cone is no longer present. Therefore, it is possible to make full use of the radiation or empty cone radiation to obtain the required sound pressure. When the vibration frequency is further increased, the vibration of the duct or the empty cone begins to weaken, and the vibration of the speaker begins to increase. At this time, the phases are almost the same, so they are like the crossover frequency of the two-way speaker, and the sound pressure is 88.JPG superimposed.