Passive Crossover Frequency Calculator
Splitting the signal between drivers
A passive crossover uses an inductor-capacitor network to split an audio signal between speaker drivers without needing any external power - frequencies below the crossover point pass to a woofer through the inductor, while frequencies above it pass to a tweeter through the capacitor.
Worked example
For a 1.5mH inductor paired with a 10uF capacitor:
fc = 1 / (2π x sqrt(0.0015 x 0.00001)) = 1299.49 Hz
This crossover point protects each driver from frequencies it isn't designed to handle - sending low frequencies to a tweeter risks damage and distortion, while sending high frequencies to a woofer wastes power on frequencies it can't reproduce cleanly.