The difference between different types of subwoofers

                       The difference between different types of subwoofers

There are active subwoofers and passive subwoofers. At present, the most popular subwoofer in home theaters is the active subwoofer. After all, the subwoofer needs a lot of power to work, and many AV amplifiers do not have enough driving force. Therefore, passive subwoofers are more common in the field of custom installation. The external power amplifier design can not only ensure that the subwoofer adopts a slim body so that it can be better embedded in the wall, but also has better control over the heat dissipation of the power amplifier. It is conducive to the long-term work of the sound.

The active subwoofer is a built-in power amplifier module. At present, the mainstream configuration of most home theaters is an active subwoofer.

According to the mode of action when working, the subwoofer has the difference between closed type and reflective type. Closed subwoofer, as the name suggests, the entire box is closed, and the low-frequency output is performed through the air compression inside the box, while the reflex subwoofer leads the back radiation wave of the unit through a pipe. This pipe is the well-known phase inverter. hole. Generally speaking, the phase port is circular, and only one is equipped, but some subwoofers may also design two or more phase ports in order to facilitate the user to adjust the output energy and improve the sense of hearing. High degree of fusion and aesthetics, some subwoofers even have bar-shaped port design. For a closed subwoofer, it often has a faster response speed and clear low-frequency details. On the contrary, a reflex subwoofer with the same specifications will have more advantages in terms of energy. Therefore, you can choose a subwoofer according to your own preferences. If you like energy, choose the reflex type, and if you like speed, choose the airtight type.

The phase port of the reflex subwoofer is divided into circular and strip-shaped, and the phase port of most subwoofers is circular.

In most cases, subwoofers are designed with only one woofer, especially for small-sized subwoofers. However, in order to adapt to larger spaces and output stronger energy, subwoofers with dual-unit design are more and more popular among users. It should be noted that the subwoofer of the dual-unit configuration is usually designed as a closed box. After all, this type of subwoofer has "inherent disadvantages" in terms of energy. Subdivided down, the dual-unit subwoofer has different differences between "true dual unit" and "unit + radiator". "True dual unit" is easy to understand, that is, two real units are piled up. At present, there are two completely different designs of dual unit subwoofers on the market. One is a push-pull design, and the two units are respectively installed on the On the front and bottom of the box, the phases of the two units are opposite when they work, and the reaction force is generated by the air compression inside the box. The advantage of the push-pull design is that the output energy is strong, and at the same time, nonlinear distortion can be well controlled. Another dual-unit configuration scheme is a two-way sound design. The two units are symmetrically distributed on both sides of the cabinet back to back, and have the same phase characteristics when working. It is inevitable to increase energy output. Another advantage of two-way sound is that it effectively suppresses the sound of the box. The vibration of the body ensures that the subwoofer can be as stable as Mount Tai when it outputs loud pressure.

Push-pull design subwoofer, the two units work in opposite phases

Two-way sounding subwoofer, two units distributed back to back, the same phase

"Driver + radiator" is becoming popular as another common design scheme. Some manufacturers will include the radiator in the unit configuration and call it "another unit" of the subwoofer. There is some truth to this claim, since the radiator is essentially a woofer without a voice coil or magnet. According to different needs, a subwoofer can be equipped with one or two radiators at the same time. The radiator needs to rely on the active unit to function. More radiator configurations can make the energy output of the subwoofer stronger. It is worth noting that both the "true dual unit" and "unit + radiator" schemes require the power amplifier to provide strong driving force, so you can see that high-power power amplifiers are often standard for this type of subwoofer. As for the "true dual unit" and "unit + radiator" how to choose? From a theoretical point of view, of course, the effect of "true dual unit" is better, but the resulting cost increase also needs to be seriously considered.

"Unit + Radiator" is one of the common designs of sealed subwoofers, which greatly helps to enhance the sense of volume

Using reflected sound to enhance energy is a common design of reflective subwoofers. In this solution, the woofer is generally placed at the bottom of the box to enhance the sense of low-frequency volume through ground reflection. In addition, this type of subwoofer will also be positioned There is more room for manipulation. As mentioned above, some reflective subwoofers are equipped with multiple phase-reversing holes. In most cases, the manufacturer will provide a special sponge plug. The function of the sponge plug is to adjust the size of the energy output and the response speed. Plugging it into the port can change the low-frequency hearing. When using the sponge plug, please note that some subwoofers need to adjust the parameter settings of the subwoofer at the same time to take effect, so be sure to read the manual carefully when adjusting your subwoofer. Completely avoid the risk of occasional rollover! Using a sponge plug can change the hearing of the subwoofer to a certain extent