What is a Crossover
Crossovers are essentially filters that separate or block frequencies and route them to the correct speaker. There are two common types of crossover,”passive” and “active”.
Passive crossovers are non-powered and are most commonly used with component systems in-line with the speaker wires located between the amplifier or head/source unit and speakers. They are also used in fullrange speakers. Both two and three way speakers have passive crossovers to separate or block the frequencies for the mid and/or tweeters to ensure the appropriate frequencies are delivered to the respective driver.
Active crossovers are electronically powered units that are placed in-line with the RCA signal lead between the head unit/source and the amplifier.
They will provide better signal separation and unlike passive crossover there is no power loss.
There are three main types of crossover filters. High-pass filter, low-pass filter, and a subsonic-filter.
A high pass crossover allows high frequency signals in the 5kHz-20kHz range (generally) to be passed to the speaker/tweeter and the lower frequency signal is blocked.
A low-pass crossover allows the low frequency signal in the 50Hz-250Hz range (generally) to be passed to the speaker/sub and the higher frequencies are blocked.
A subsonic filter is essentially a high-pass crossover which blocks the frequency signal generally from 10Hz-40Hz this signal often contains no music and its removal will improve woofer control and sound quality.