How Does a Subwoofer Work? 

Subwoofer speakers are familiar to most of us. Whether you want an enhanced listening experience to dynamic pop music or watch Hollywood blockbusters, a good subwoofer can give us stunning sound effects. However, do you know about this kind of product? Today we will have a deeper look into it. If you are going to buy a bass speaker, this article is worth reading carefully.  

What is a subwoofer?

A subwoofer is a type of speaker that can produce low-frequency sounds known as bass and sub-bass. Typically, most subwoofers can render lower frequencies in the range of about 20–200Hz. Theoretically, it is hard for us to hear low-frequency sounds. However, thanks to the subwoofer, these low-frequency sounds can be reproduced with shocking effects. For example, it can allow you to feel the impactful movie sounds of a blockbuster in your chest or down your spine instead of just hearing them. 

How does a subwoofer work? 

When trying to understand the working principle of a subwoofer, you will find that subwoofers are classified into two categories: passive and active subwoofers. Passive subwoofers are powered by an external amplifier, while active subwoofers, also called powered subwoofers, use an internal amplifier and a line-level crossover, which enable them to provide high-quality sound while allowing you to adjust the frequency range of the subwoofer, which makes it a mainstream style on the bass speaker market. 

Powered subwoofers usually come in a small body, which means that their horn unit is small (usually with a diameter of 2 or 3 inches or a diameter of 5 to 6 inches). However, the size of a horn unit can directly affect how much air it can push, which influences the low-frequency sound performance. The bigger the horn, the more energy it can generate. Theoretically, these small, powered subwoofers can not bring you a powerful bass sound without a big horn to offer enough energy. But mini subwoofers, offered by BWOO, can always provide us with uncompromising low-frequency performance thanks to the application of passive radiators.  

You may be confused about what a passive radiator is. 

Passive radiators, also called passive diaphragms, have a similar structure to horn units. Both have a diaphragm that pushes air and the rings needed to restore the diaphragm to its normal position. But the difference between them is that the passive radiator can not be powered by electricity. That is to say, it can't make a sound by itself. 

Then, how does a passive radiator work?

A powered subwoofer usually contains an active speaker and a passive radiator. The passive radiator is driven by the air pressure brought in by the active speaker. Concretely speaking, when pronouncing a sound, the active speaker generates vibration, which will cause strong air pressure in the box. However, as they work in a sealed box, the air pressure inside the speaker fails to go anywhere else but out through the passive radiator. As a result, a powerful bass effect forms. 

Besides, a passive radiator can be installed either on the bottom or the back of the box, so we can use a larger passive diaphragm to enhance the air volume it can push to reinforce the low-frequency sound. Meanwhile, the increase in the size of the passive diaphragm can also reduce the resonant frequency so that the speaker can deliver a deeper bass. As such, even a small speaker can produce a magnificent bass effect. 

IPX Waterproof Rating 

Besides excellent sound quality, the waterproof function of the speaker is also vital if you want to buy one for outdoor activities like camping, swimming, hiking, or climbing because it may be easy to ruin it if it rains or meets sudden water slashes. 

When shopping for a speaker, we often see a term like IPX7. IPX, an international waterproof level certification system, is the key element for measuring the water protection ability of the device. The term "IP" stands for "Ingress Protection" which measures how well a device survives both solid objects and liquids. 

According to the IPX waterproof level certification system, the IPX waterproof rating has 8 levels, from IPX-1 to IPX-8. The details are as follows: 

IPX0: without protection from water

IPX1: Can resist water drops that fall vertically onto the product.

IPX2: Can resist drops of water that fall on the product at a 15° angle or less.

IPX3: Can survive spray-like water droplets at 60 degrees from the vertical 

IPX4: Protected from water splashes from any direction

IPX5: Can resist a continuous, low-pressure water jet spray.

IPX6: Can withstand high-pressure water jets from any angle 

IPX7: Can survive a 30-minute immersion in water of up to 1 meter without any damage.

IPX8: Can withstand immersion in water deeper than 1 meter. 

In terms of the selection of waterproof speakers, at least IPX4 certified or above is suggested if you are looking for an outdoor speaker and are going to place them beside a swimming pool. However, for some music to enjoy the sunshine beside the beach, diving, or hiking, try to choose a speaker that at least boasts a waterproof rating of IPX7 or IPX8 in case of unexpected emergencies. 

How is a waterproof speaker made?

According to the information mentioned above, you may have a basic understanding of which waterproof speakers you should settle on. However, to better protect your waterproof speakers, it is still necessary to know what makes a speaker waterproof. Simply put, waterproof speakers come with multiple protections from water damage. 

Conformal Coating 

Conformal coating is the first important protection layer to protect a device from water damage. It not only effectively protects printed circuit boards from things like solid debris, salt, chemicals, and moisture, as well as from temperatures that are too hot or too cold, but also helpfully prevents the damages brought by things like UV rays, humidity, and corrosion on the important electrical marine audio parts. 

However, it is not a completely sealed layer, but it can bring good breathability to the PCB boards to allow water vapor that gets trapped to escape, thereby prolonging the lifespan of the speaker. 

Nanotechnology

Nanotechnology is a very important technology for forging an outdoor speaker. It uses small particles to create an oil-proof, UV-protective, and water-resistant coating. And this coating is usually made from a compound called fluoropolymer. It works by making molecules and atoms of this compound get into the smallest cracks, crevices, and gaps to protect the circuitry from chemicals, dust, salt, and corrosion that could damage it.

Superhydrophobic Coating

Waterproof speakers provided by excellent manufacturers like BWOO will come with another special protective coating called a superhydrophobic coating. It is considered a completely sealed protective layer against water. In essence, it is also a super-nanoscopic layer made from many kinds of materials, such as zinc oxide polystyrene and manganese oxide polystyrene nanocomposite, which can protect speakers and PCB boards from water. Once the water touches the coating, it will rebound. Therefore, it can effectively prevent your device from getting damaged by liquid and vapor water.

Tapes and glue 

Apart from the mentioned above, tape and glue are also often used to make a waterproof speaker. Because of the ports and joints available in speakers, water can still damage them. Many manufacturers try to form a watertight seal using tape and glue to cement all the relevant components together. 

Conclusion 

Whether you're purchasing a speaker for home or outdoor use, there is no reason to reject a bass speaker, as it always brings us a thrilling sound experience. However, in terms of buying an outdoor speaker, we can not make a compromise on the water resistance. Luckily, BWOO provides us with a subwoofer that comes with superior sound performance and professional waterproof features. So why not shop for it today? Please check out our site to get more options for high-quality bass speakers.