Low-pass filter - how to achieve an excellent sound?

A lot of people are interested in the low-pass filter, which is necessary for a subwoofer. Usually the human ear can perceive sound, starting from 20 and ending with 20 thousand Hertz. And notes, the sound of which occurs at the lower limit, is the bass. Accordingly, at the upper limit, the sound is more like a squeak. For those who want to learn how sound sounds at different frequencies, a specially created program that does not require separate installation is specially created. You only need to download and enable it. The interface of the program, too, will not cause any special difficulties.

When studying what a low-pass filter is, you should not forget about the cut-off frequency, the increase of which is not necessary. When making a subwoofer, it is done so that the lower frequencies sound unchanged, while the upper frequencies are transmitted with considerable distortion. To do this, use a special filter, which removes all too high sound.

The subwoofer should meet the following parameters: the smaller the bass speaker in the speaker playing with it, the higher the cutoff frequency of the filters used in the sub. In other words, if the speaker has a 10 cm bass speaker, then the cutoff frequency should reach three hundred Hertz. If the size of the bass column is equal to thirty centimeters, then the filter cutoff frequency reaches a hundred Hertz.

But if the subwoofer has a small speaker, then most likely it will not be able to reproduce very low frequencies. If the situation is reversed, then the sub will be able to recreate the low frequencies. That is, a good subwoofer can be determined by how well it can resume low frequencies. Higher frequencies are usually reproduced by the subwoofer with very strong distortion.

In general, the cutoff frequency does not cause any complications. It remains to disassemble the low-pass filter itself. It can be passive or active. In the first case, the filter is a huge inductor with several capacitors. In this case, there is no need to install separate amplifiers. Also, no need to install additional power supply. Passive filter must be connected directly to the dynamics of the subwoofer.

Another thing that you need to know when studying this topic is the steepness of the recession, which is a special parameter that shows how much the sound is muffled at a level above the cutoff frequency. Usually, when installing filters, the disappearance of sound at a high frequency should occur smoothly, without sudden drops.

Due to the fact that the low-pass filter uses a low cutoff frequency, and its order is high, the need for a passive design is eliminated. In this case, you must use an active filter. Its drawback is the mandatory requirement in a separate power supply and amplifier on the subwoofer channel. In addition, in some cases, you may need an adder.

On this basic parameters, which has a low-pass filter, end.