Speaker Crossover Calculator
2-way splits between woofer and tweeter; 3-way adds a midrange driver
Higher order = steeper rolloff slope
-6 dB at crossover, flat summed response, in-phase outputs. Best for hi-fi.
Frequency at which signal transitions from woofer to tweeter
Enter Crossover Parameters
Set your crossover type, filter order, filter alignment, and driver impedances to calculate capacitor and inductor values for your crossover network.
How to Use the Speaker Crossover Calculator
Select Your Crossover Configuration
Choose between a 2-way crossover (woofer + tweeter) or a 3-way crossover (woofer + midrange + tweeter). Then select the filter order (1st through 4th) and the filter alignment. For most home hi-fi applications, start with 2nd or 4th order Linkwitz-Riley for its flat summed frequency response and phase-coherent outputs.
Enter Driver Impedances and Crossover Frequency
Enter the nominal impedance of your woofer and tweeter in ohms (typically 4, 6, or 8 Ω). Use the quick-select buttons for common values. For 2-way designs, enter a single crossover frequency (2,000–4,000 Hz is typical for home hi-fi). For 3-way designs, enter both the woofer-to-midrange frequency and the midrange-to-tweeter frequency, ensuring a ratio of at least 8:1 between them.
Review Component Values and Charts
The calculator shows the capacitor (µF) and inductor (mH) values for each section of your crossover. The horizontal bar chart lets you visually compare component sizes across sections. Note any phase polarity warnings — for even-order Butterworth, Bessel, or Chebyshev designs, you must reverse the tweeter's polarity. For 3-way designs, check the frequency spread ratio indicator.
Use Zobel and L-Pad for Precision
Expand the Advanced Options section to access the Zobel network calculator and L-pad calculator. Enter your speaker's DC resistance (Re) and voice coil inductance (Le) from the datasheet to calculate the Zobel components that will flatten the driver's impedance rise. If your tweeter is significantly more sensitive than your woofer, use the L-pad calculator to find resistor values that match sensitivity levels. Export your complete parts list to CSV or print it for use at the workbench.
Frequently Asked Questions
What is the best filter alignment for a 2-way home hi-fi speaker?
Linkwitz-Riley is widely considered the best choice for home hi-fi crossover design. A 4th-order Linkwitz-Riley (formed by cascading two 2nd-order Butterworth filters) offers a 24 dB/octave slope for excellent driver protection and isolation, places both outputs at -6 dB at the crossover frequency, produces outputs that are in-phase with each other (so no tweeter polarity reversal is needed), and sums to a perfectly flat combined frequency response on-axis. Its only disadvantage over lower-order designs is requiring more components (two capacitors and two inductors per section). For a simpler build, a 2nd-order Linkwitz-Riley is also excellent and uses fewer components.
Why do I need to reverse the tweeter polarity for some crossover designs?
Even-order filters (2nd-order and 4th-order Butterworth, Bessel, and Chebyshev) introduce a 180° phase shift between the high-pass and low-pass outputs. At the crossover frequency, where both drivers are contributing equally, this phase difference causes their acoustic outputs to partially cancel each other, producing a dip in the summed frequency response. Reversing the tweeter's polarity (connecting its positive terminal to the crossover's negative output terminal) corrects for this, allowing the two outputs to sum coherently and produce a flat overall response. Linkwitz-Riley designs are the exception — their outputs are in-phase at all frequencies, including the crossover point, so no polarity reversal is needed. Odd-order filters (1st and 3rd) naturally produce coherent summation without reversal.
What crossover frequency should I use for my 2-way speakers?
The optimal crossover frequency depends on the capabilities of your specific drivers. As a general guide: home hi-fi 2-way systems typically cross over between 2,000 and 4,000 Hz — a common choice is 3,000–3,500 Hz, which is high enough that the tweeter operates well above its resonant frequency while low enough to keep the woofer in its range of good performance. Car audio often uses 3,000–6,000 Hz due to the need for sharper driver separation in smaller enclosures. For a subwoofer crossing to a full-range driver, 80–120 Hz is standard. Always check the frequency response graphs of your actual drivers — the crossover should be placed in a region where both drivers have overlapping, flat response.
What is a Zobel network and do I need one?
A Zobel network (also called an RC impedance equalization network) is a series resistor-capacitor combination placed directly across the speaker terminals to flatten the rising impedance of a dynamic driver's voice coil at high frequencies. Without compensation, a woofer's impedance might rise from its nominal 8 Ω rating to 20–30 Ω at frequencies near the crossover point. This rising impedance changes how the crossover filter 'sees' the load, causing the actual crossover frequency to shift higher than calculated. Adding a Zobel network makes the driver appear resistive to the crossover circuit, so your calculated component values produce the intended crossover frequency and slope. It is especially important for woofers used with 1st or 2nd order crossovers; higher-order designs are somewhat less sensitive to impedance variation.
What is an L-pad and when should I use one?
An L-pad is a two-resistor attenuator network placed in series with a driver (typically the tweeter) to reduce its sensitivity to match that of another driver. Tweeters frequently have a sensitivity rating 3–6 dB higher than the woofer they are paired with. Without compensation, the tweeter will be too loud relative to the woofer, producing a bright, top-heavy sound. An L-pad uses a series resistor (R1) to drop voltage before the tweeter and a shunt resistor (R2) to maintain the correct impedance seen by the crossover network. Enter the impedance of the tweeter and the number of decibels of attenuation needed into the calculator to get the R1 and R2 values. The main limitation of an L-pad is that it dissipates power as heat, reducing efficiency — a level control potentiometer (which is essentially a variable L-pad) is used in many commercial speakers for adjustable tweeter level.
How do I convert calculated values to standard component values?
Calculated crossover component values are ideal values that will rarely match standard commercial component values exactly. Capacitors are commonly available in E12 or E24 series values, and audio-grade crossover capacitors are typically available in values like 2.2, 3.3, 4.7, 6.8, 10, 15, 22, 33, 47, and 68 µF (and multiples thereof). For a capacitor calculated at 13.2 µF, you might combine a 10 µF and a 3.3 µF in parallel, giving 13.3 µF — very close to the ideal. Inductors are available in standard values from approximately 0.1 mH to 10 mH; combining them in series is straightforward. Aim for within 5% of the calculated value, which will shift the actual crossover frequency by approximately 2.5%. Using a higher crossover calculator precision is most important for the tweeter crossover frequency, as tweeters are more sensitive to operating below their recommended frequency.