The basic principles of selecting a subwoofer in a home theater

It's hard to imagine modern home theater without subwoofer. It is he who delivers to the viewer powerful thunder, frightening sounds of shots, the roar of a motorcycle. If this range of sounds is not realistic, then the presence effect is lost when watching a blockbuster. A home cinema subwoofer affects the reproduction of deep, dramatic bass.

Subwoofer functions

The subwoofer solves the problem of cutting off the low-frequency spectrum of the input signal going to the loudspeakers. This frees them from bass overload, and the acoustic reproduction image becomes more realistic and voluminous. Separate sound combinations, such as, say, the sound of drums, are reproduced in the home theater. active subwoofer.

In principle, subwoofers are a collection of individual loudspeakers, the purpose of which is to reproduce exclusively low-frequency sounds.

The family of sabs is very large, and, accordingly, the problem of choosing a device for a particular home theater arises. When optimizing it is necessary to understand the structural differences in the line of subwoofers. Three types are most widely represented:

• phase inverter;
• strip;
• closed.

Briefly describe all types, since the design features of the case often determine the acoustics of the system.

Choice of acoustics

When the dynamic head is isolated in a separate enclosure, this design is referred to as closed. Advantages of this solution:

• constructive simplicity;
• the exit surface does not give "leaks";
• minimum signal delay.

Subs of the closed type reproduce the most intense and deep bass. However, to play a full, deep bass requires a significant amount of body. Such subwoofers are usually bulky and heavy. There are also small-sized options, but they are extremely expensive.

Subwoofers phase inverter type Consist of a case with a main speaker inside.A specially planned opening is made in one wall of the housing. The bass sound of this design and louder and more powerful. The oscillatory acoustics system works according to complex physical laws and requires mathematical calculations.

The disadvantage of this decision is a great pickyness to fine tuningotherwise there will be serious distortion.

The combination of the above options creates a concept band subwoofer. This is almost an elementary bandpass filter. The case of such a subwoofer is assembled from two compartments, one of which is a phase inverter, and the other is a deaf box. Thanks to this solution, the sound pressure is significantly increased, but the frequency range is narrowed. The output sound is extremely powerful, but even a small error in tuning further narrows the frequency range.

Thus, it is obvious that choosing the best subwoofer is extremely difficult. Each type has its advantages and disadvantages, and the final decision depends on the specific conditions. For example, bass-reflex constructions are famous for excellent feedback, while the closed ones are used to reproduce deep bass.

But there is another classic separation of these devices according to the following parameters:

• with the presence of a built-in amplifier (active);
• without built-in amplifier (passive).

The choice between active and passive subwoofer

Under active subwoofer means a device with a built-in amplifier in its package. When properly tuned, it guarantees a high level of signal without distortion, thanks to a reduction in the load from the main speakers when the bass is played.

If the amplifier is missing, then we are dealing with passive option. It is much cheaper, but the owner will be forced to engage in painstaking adjustment of matching the subwoofer with other components of the speaker system - in columns. Active sub more expensive, so the choice between the types of devices often lies in the financial plane.

Active subwoofer well shows its qualities in large rooms.

Sizes and power

The size of the subwoofer is uniquely large, and they look, as a rule, cumbersome. Attempts to independently disassemble the column and reduce its size lead to disastrous results. There are no small sabs with good and powerful bass, it is impossible taking into account the laws of physics. The decrease in volume in relation to the size of the head significantly affects the nonlinear distortion coefficient.So it must be reconciled with the thought that a quality subwoofer is necessarily bulky.

There is a small amount compact sabswhere the problems of distortion trying to deal with electronics and filling the case with special materials. But these options are very expensive.

By power, the subwoofer must be chosen in direct proportion to the size of the room. The basic rule is: the larger the speaker, the deeper the bass.

The sound waves of low frequency diverge evenly in all directions. Accordingly, the possibilities of placing the subwoofer are endless. The choice of location of the device is carried out by ear in installation process. In a simple home theater, one sub is used, but real, real special effects are obtained only with two subwoofers. In any case, the principle of symmetry of acoustic placement should be preserved.

There is no diversity in the external performance of these devices. They are stably placed in a cube-shaped case or close to it. Much effort is needed to find something out of the ordinary in shape. As a rule, experts who can disassemble the body, can modify it.The colors are dominated by black and white tones or wood structure.

Quality bass for the car

A car enthusiast and overnight a music gourmet will never give up the installation subwoofer in the car. Especially if you make a good noise insulation of the cabin. But before you disassemble the machine with your own hands to install a subwoofer in it, you must carefully consider the narrow places of this design. First, you need an amplifier, the radio does not swing the subwoofer. Secondly, such acoustics are designed for “greenhouse” conditions. In a car, the temperature and humidity change over a wide range throughout the year, and the acoustics system can easily crack.

Before installing the sub, you need to disassemble yourself and slightly strengthen it. You can eliminate several powerful transistors, thereby reducing consumption. You also need to disassemble the rear panel of the car to install the speakers, and solve the problem of choosing between active and passive devices.

Setting up the subwoofer should be done by experts, as the space in the car is extremely limited. The financial costs of the arrangement are large enough, and if you spend 20 minutes in a car a day, you should consider whether such an expensive rework is necessary.

We select a subwoofer

Let's pretend that all elements of home theater already purchased, you need to select only the sub. What type of case is suitable? Since, at home, a large volume level is not needed, the bass-phase inverter option disappears. The band sub sounds in a rather limited range, and its cost is quite large.

The most suitable scheme is a closed enclosure. Such a device reproduces a rich bass and is not very susceptible to external conditions.

If you buy a subwoofer for home theater, then you can safely assume that there is no preamp in it. In this case, it is reasonable to make a choice in favor of an active subwoofer. The power of the device must be in harmony with the power of the front speakers.

When the subwoofer is located far from the amplifier, it is inconvenient to pull the cable, and the loss must be taken into account. The situation will be able to connect to wireless system. Now there are sets of wireless adapters, and then you can fully enjoy the rumble of sound effects, without fear of tripping on the cable.