A crossover splits the music so low notes go to the woofer and high notes to the tweeter. Higher orders give steeper slopes (6 dB/octave per order) and protect tweeters better, at the cost of more components.
How to use the Speaker Crossover Calculator
- Filter alignment
- Tweeter impedance
- Woofer impedance
- Crossover frequency
Results update as you type, every field has its own unit menu, and everything is calculated in your browser.
How it works
Choose the alignment, enter the tweeter and woofer nominal impedances and the crossover frequency.
Inputs explained
| Field | What to enter |
|---|---|
| Filter alignment | Choose one: 1st order (6 dB/oct), 2nd order Butterworth (12 dB/oct), 2nd order Linkwitz–Riley, 2nd order Bessel … |
| Tweeter impedance | Units: Ω, kΩ, MΩ, mΩ |
| Woofer impedance | Units: Ω, kΩ, MΩ, mΩ |
| Crossover frequency | Units: Hz, kHz, MHz, GHz, THz, rpm |
What each result means
- Tweeter capacitor C2 = 0.3183÷([Tweeter impedance]×[Crossover frequency])
- Woofer inductor L2 = 0.0796×[Woofer impedance]÷[Crossover frequency]
Example values
How the main result changes when Tweeter impedance changes and everything else stays at the example values above:
| Tweeter impedance (Ω) | Tweeter capacitor C1 (µF) |
|---|---|
| 4 | 11.25 |
| 6 | 7.5 |
| 8 | 5.625 |
| 10 | 4.5 |
| 12 | 3.75 |
| 16 | 2.8125 |
Formula
1st order: C = 0.1592/(R_t·f), L = 0.1592·R_w/f · 2nd Butterworth: C = 0.1125/(R·f), L = 0.2251·R/f
2nd Linkwitz–Riley: C = 0.0796/(R·f), L = 0.3183·R/f · 2nd Bessel: C = 0.0912/(R·f), L = 0.2756·R/f
Worked example
Inputs — Filter alignment: 2nd order Butterworth (12 dB/oct); Tweeter impedance: 8 Ω; Woofer impedance: 8 Ω; Crossover frequency: 2,500 Hz.
Results — Tweeter capacitor C1 = 5.625 µF; Tweeter inductor L1 = 0.7203 mH; Woofer inductor L1 = 0.7203 mH; Woofer capacitor C1 = 5.625 µF.
Key terms
- Crossover
- Filter network splitting frequencies between drivers.
Frequently asked questions
What crossover frequency should I use?
Typically 1.5–3.5 kHz for two-way speakers, per the drivers' specs.
Why Linkwitz–Riley?
Its outputs sum flat at the crossover point.
Should I use the nominal impedance?
It is a starting point; real drivers vary with frequency – Zobel networks help.
Does polarity matter?
Second-order designs usually need the tweeter wired in reverse polarity.