The consuming electronic products are limited in the dimension of speaker, unable to use the larger size leads to the imperfect result of the low-pitched sound. Therefore we need a good enclosure to extend the low frequency effect, which means we still need space, just the limitation of the form is not so strict. Generally speaking, the larger the capacity is, the better the low frequency we can gain, because most of the hand-held products still do not have enough space for enclosure.

When the speaker emits sound the diaphragm will move to compress the air in the enclosure. Thus the larger powered speaker needs better outlets to get the proper damping and reach the good low frequency, but the sound will not be destroyed by the resistant of the compressed air.

On the other hand, the sound will be exited at both of the front and the rear area while the speaker works, but the phase is 180 degree and the sound will be neutralized. Therefore it is very important to make sure that the front and the rear sound fields are completely separated, and there is no connection between the flowed air to avoid the neutralization of the sound.

Besides, to emit sound means the vibration will be generated, therefore the speaker also needs to be firmly fixed on the mechanism, and adds some shockproof material appropriately, such as the sponge, which can help to avoid the noise coming from vibration.

The design of the sound apertures is multi-apertured, and the amount of them is the more the better, at least exceed 1/8 area of the surface. The shapes of the sound apertures just need beautiful appearance to meet industrial design; but are requested to have a larger outward hole than inward. It means the part which is exposed to the outside air should be larger than inside