A lot of people are interested in the low-pass filter, which is necessary for the subwoofer. Usually the human ear is capable of perceiving sound, starting from 20 and ending with 20 thousand Hertz. Moreover, the notes that sound at the lower limit are bass. Accordingly, at the upper limit, the sound is more like a squeak. For those who want to know how sound sounds at different frequencies, a program has been specially created that does not require a separate installation. You just need to download and enable it. The program interface will also not cause much difficulty.
When studying what a low-pass filter is, one should not forget about the cutoff frequency, the increase of which is not necessary. In the manufacture of the subwoofer, the low frequencies are made to sound unchanged, while the high frequencies are transmitted with significant distortion. To do this, use a special filter that removes all too high sounds.
The subwoofer must meet the following parameters: the less the speaker playing with it has a bass speaker, the higher the cutoff frequency of the filters that are used in the subwoofer should be. In other words, if the speaker has ten-centimeter bass speakers, then the cutoff frequency should reach three hundred Hertz. If the size of the bass speaker is thirty centimeters, then the filter cutoff frequency reaches one 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 the opposite, then the sub will be able to recreate low frequencies. That is, a good subwoofer can be determined by how well it can resume low frequencies. A higher frequency subwoofer usually reproduces with very strong distortion.
In general, the cutoff frequency does not cause any difficulties. 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, it will not be necessary to install additional supply voltage. Passive filter must be connected directly to the subwoofer speaker.
Another point that you need to know when studying this topic is the steepness of the decline, which is a special parameter that shows how hard 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 sharp 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, an active filter must be used. Its disadvantage is a mandatory requirement for a separate power supply and amplifier for the subwoofer channel. In addition, in some cases, an adder may be needed.
On this, the main parameters that the low-pass filter has have come to an end.