For good audio systems it is a good idea to send speakers a certain frequency range, so that the speaker does not have to use inappropriate frequencies. The audio crossover was created specifically for these needs, cutting frequencies out of the working range of the speaker.
If you have a 2-way speaker, you will need a 2-way crossover, consisting of a low-pass filter for the mid/bass and a high-pass filter for the tweeter treble, in this case we will have a single cut-off frequency that should be commonly chosen between 2,000 and 3,000 Hz.
If you have a 3-way speaker, we will use the 3-way crossover, which consists of a low-pass filter for the woofer, a band-pass for the midrange and high-pass for the tweeter, in this case we will have 2 cut-off frequencies, usually one between 400-500 Hz and the other between 4,000-6000 Hz.
There are two types of crossover:
- Passive, it is the most common type, cheapest and easiest to install. It is usually placed near the speaker or on it, and in any case after the amplifier.
- Active, is generally placed between the preamplifier and the amplifier, has the advantage of offering the adjustment of the filter, but with the disadvantage of having to install a separate amplifier for each cut.