This is because the signal has not been amplified yet. Active crossovers are more efficient with amplifier power than passive, because they do not dissipate amplifier power. They can use lower power amplifiers to receive the same output level viii. Placed between the power amplifier and the speaker ii. The passive crossover interacts with the impedance of the speaker iii.
Passive crossovers have less parts, because it doesn t have a buffer stage or a power supply iv.
Parts cost more for passive crossovers because they deal with more power v. Passive crossovers fit inside loudspeaker enclosures vi. They usually contain one resistor, which consumes power that will not find its way to the speaker, making the speaker less efficient. A single three-way loudspeaker can be run off one amplifier channel making it very cost effective. Although crossover design contains many equations and variables there is some experimentation and trial and error involved. All of these equations provide a perfect theoretical design, but in reality your ears should be making the decision on the final design.