Active subwoofers, which is also known as a Powered sub, is a loudspeaker that is designed to produce low- pitch sound frequencies. These frequencies are generated by a loudspeaker driver called a woofer. The frequencies of a sound wave depends on what the product is being used for. For example, consumer subwoofers will produce 100hz and above, whereas a subwoofer used for professional live sound will generate less than 100hz. A THX-approved system will turn out below 80hz.
An active subwoofer is made with a built-in amplifier. This makes it different from a passive subwoofer because it has the amplifier built into the enclosure and driver. Also a passive subwoofer needs to be connected to an external amplifier to power its low frequency sound, whereas active subwoofers do not need a separate amplifier.
A subwoofer can enhance the low-bass range of a normal loudspeaker system and can work at higher volumes. It is made up of one, two or more woofers that are put in the amplifier enclosure. They are available in lots of designs which have the bass reflex with a vent or port. Also, subwoofers are made to withstand air pressure and to resist deformity. This is because of the good quality wood that they are made from. They are used to produce deep bass frequencies.
A subwoofer can be used as part of your home cinema system or in your car stereo. It uses a built-in amplifier and a larger woofer to improve the quality of deep bass sounds, if it has a built-in amplifier then it has to be connected to an electrical outlet. Low frequency signals are not directional , but high frequencies are. This means that the subwoofer can be moved around more than placement-sensitive speakers.