Now, according to the different structural box classification, closed box, vented enclosure, labyrinth speakers, speaker and acoustic pipe multi-cavity resonator type speakers. Today, to introduce common to both speakers - Speaker closed and vented enclosure.
Closed box structure which in addition to the rest of the speaker holes are sealed, is divided into two mutually unvented space before and after such a speaker cone paper, a box is infinite outer space having a certain volume of the closed inside the space.
The advantage of closed box:
1) isolated from each other since the space inside and outside the housing, similar to the infinite baffle loudspeaker acoustic radiation is not transmitted back to the tank outside front speakers acoustic radiation interfere to prevent acoustic short-circuit;
2) pure tone, bass better resolution;
a simple 3) structural design.
The disadvantage of the closed box:
1) as attached to the cone with the spring due to the air inside the speaker cone vibration is continuously expanded and compressed, so that the inside air to produce an additional elastic force to the vibrating cone, , so that the natural frequency of the speaker to improve;
2) Since the speaker can substantially opposite the radiation is absorbed and wasted, and thus low efficiency.
The vented enclosure structure other than the speaker hole is opened, on which the panel further phase hole is opened, and Konghou An inverting means inverting the tube. Air tube inverted cone and play a similar role in the formation of an additional acoustic radiator.
Advantage of vented enclosure of:
1) was poured through rational design size with the hole, so that the sound waves from the front speakers radiated sound radiation from the inverting holes are superposed, thus enhancing the radiation energy of sound waves, especially low sound frequency band energy, high work efficiency.
2) Due to phase down the hole, not only inside the acoustic energy is released, while also balancing the inside and outside air pressure. Thus reducing the amplitude distortion near the low frequency speaker of the lower limit frequency.
The disadvantages of vented enclosure:
1) poor transient characteristics of the low frequency sound performance a bit muddy. This is because the negative speaker sound waves to take some time out from the inverter in the housing hole, superimposed on the front of the sound wave, which there is a question of time delay. Strictly speaking, the human ear to hear the sound waves coming from the front speakers, and then came back to hear the speakers sound waves. However, due to the reaction of the human ear is not as good as high-frequency low-frequency sensitive, it will not have much impact;
2) design and adjustment more difficult, prone to bad design is too heavy bass sound is too loud or air flow and other issues.
In general, for the same volume and the same size of the speaker closed box and vented enclosure, low distortion closed box, "true" bass and low efficiency. Vented enclosure low frequency performance better, "false" bass and high efficiency. So, you will choose which speakers it?
