A physical question, can sound absorbing sponges play a shock absorbing role 10

When the speaker cabinet is not strong enough - when the cabinet follows the subwoofer vibration, the phase of the cabinet is just the opposite of the speaker phase, which will cause the low-frequency signal of the speaker to be weakened by the low-frequency signal emitted by the cabinet vibration, which seriously affects the low-frequency performance of the speaker, in order to overcome the low-frequency signal generated by the cabinet vibration, sound-absorbing cotton can be installed in the cabinet, its function is to weaken the impact of the sound wave emitted from the back of the speaker on the cabinet, so as to avoid the vibration of the cabinet, so the general speaker will be installed inside the sound-absorbing cotton, but, Since the sound-absorbing cotton absorbs the sound waves, the sound waves from the pilot hole are weakened, which will also lead to a decrease in bass performance, because the bass of the speaker needs the superposition of the sound waves from the guide hole and the sound waves on the front of the speaker to enhance the sound wave benefit, therefore, the amount of sound-absorbing cotton placed needs to be determined by the following factors:

1.Robust or not: If the cabinet is so sturdy that it can overcome resonance with the woofer, the acoustic foam can be used with little or no use.

2.Whether the speaker is guided or closed: Since the closed speaker does not require a pilot hole to transmit sound waves from the back of the speaker, a little more sound-absorbing cotton can be installed in the cabinet to eliminate as much vibration as possible to achieve the best bass performance.

Yes, sound is caused by air vibration, and it is also a type of vibration, so the suction sponge can also absorb shock.

Of course, you can, even if you put straw, rags or something, you can also absorb shocks.

There are many small pores in the sponge, and when sound enters the porous material, the sound energy is converted into heat energy and absorbed.

When the sound wave encounters various solid materials in the early mode during propagation, part of the sound energy is reflected, part of the sound energy enters the material and is absorbed, and a small part of the sound energy is transmitted to the other side.

Any material has some sound absorption ability to the incident sound energy to a greater or lesser extent, and the material with an average sound absorption coefficient exceeding it is called a sound-absorbing material. The characteristics of the sound absorption frequency of porous sound absorbing materials are: the sound absorption coefficient of medium and high frequency is large, and the sound absorption coefficient of low frequency is small.

Sponge is a kind of hollow material, when the sound enters the sponge, it will propagate in the hollow fiber (or skeleton), part of the sound wave due to multiple fiber obstruction, sound energy will be transferred to the fiber, the fiber will get kinetic energy after the movement, friction, and finally the energy will be converted into heat energy to consume, so as to achieve a very vivid "sound absorption" phenomenon. The thicker the thickness of the sponge (however, it must be an open-pore sponge.) The greater the proportion of sound consumption in a closed-cell sponge (a sponge belonging to the closed-cell class with a large number of light reflection highlights), the higher the sound absorption coefficient (up to 1 or less).

The sound-absorbing sponge is made of melamine foam, which has unique comprehensive properties such as sound absorption, heat insulation, flame retardant, high temperature resistance and light weight. It is widely used in architectural decoration, transportation vehicles, water ships, aerospace, mechanical and electrical equipment, industrial sound absorption and thermal insulation and other fields. Sound-absorbing sponges are mainly divided into the following types: