2-Way Crossover Design / Calculator Help
Crossovers are used to filter frequencies from a driver. A High Pass Filter (HPF) filters low frequencies
and a Low Pass Filter (LPF) filters out high frequencies. Crossovers are necessary to prevent overlap in
frequency responce from different drivers in a system, and to prevent a driver from producing frequencies it
was not designed for.
You should be aware that crossovers can produce phase shift problems. A second order crossover will shift
the phase of each speaker 90 degrees, so that both speakers are 180 degrees out of phase. This means that
at the crossover frequency, the two drivers will be moving in opposite directions at the same time.
They will cancel each other out, and produce a 30db dip in the frequency response at the crossover
point. Reversing polarity of one (but not both) of the speakers will limit this dip to +- 3db. You can find
more information on phase shift at the end of the
crossover faq.
In the following formulas, use the tables to look up the
cratio and
lratio values.
The results are multiplied by 1,000,000 and 1,000 to change F and H into uF and mH values.
1st Order Crossovers
 |
Rh = Driver Impedance of the High Freq Driver in Ohms
Rl = Driver Impedance of the Low Freq Driver in Ohms
f = Crossover Frequency in Hz
 |
| Butterworth | Solen Split |
|---|
| cratio1 | .1590 | .1125 |
|---|
| lratio1 | .1592 | .2251 |
|---|
2nd Order Crossovers
 |
 |
| Linkwitz-Riley | Butterworth | Bessel | Chebychev |
|---|
| cratio1 | .0796 | .1125 | .0912 | .1592 |
|---|
| cratio2 | .0796 | .1125 | .0912 | .1592 |
|---|
| lratio1 | .3183 | .2251 | .2756 | .1592 |
|---|
| lratio2 | .3183 | .2251 | .2756 | .1592 |
|---|
3rd Order Crossovers
 |
 |
| Butterworth | Bessel |
|---|
| cratio1 | .1061 | .0791 |
|---|
| cratio2 | .3183 | .3953 |
|---|
| cratio3 | .2122 | .1897 |
|---|
| lratio1 | .1194 | .1317 |
|---|
| lratio2 | .2387 | .3294 |
|---|
| lratio3 | .0796 | .0659 |
|---|
4th Order Crossovers
 |
 |
| Linkwitz-Riley | Bessel | Butterworth |
|---|
| cratio1 | .0844 | .0702 | .1040 |
|---|
| cratio2 | .1688 | .0719 | .1470 |
|---|
| cratio3 | .2533 | .2336 | .2509 |
|---|
| cratio4 | .0563 | .0504 | .0609 |
|---|
| lratio1 | .1000 | .0862 | .1009 |
|---|
| lratio2 | .4501 | .4983 | .4159 |
|---|
| lratio3 | .3000 | .3583 | .2437 |
|---|
| lratio4 | .1500 | .1463 | .1723 |
|---|
| Legendre | Gaussian | Linear Phase |
|---|
| cratio1 | .1104 | .0767 | .0741 |
|---|
| cratio2 | .1246 | .1491 | .1524 |
|---|
| cratio3 | .2365 | .2235 | .2255 |
|---|
| cratio4 | .0910 | .0768 | .0632 |
|---|
| lratio1 | .1073 | .1116 | .1079 |
|---|
| lratio2 | .2783 | .3251 | .3853 |
|---|
| lratio3 | .2294 | .3253 | .3285 |
|---|
| lratio4 | .2034 | .1674 | .1578
|
|---|
6th Order Crossovers
 |
 |
| Linkwitz-Riley |
|---|
| cratio1 | .0884 |
|---|
| cratio2 | .1081 |
|---|
| cratio3 | .2188 |
|---|
| cratio4 | .2947 |
|---|
| cratio5 | .1783 |
|---|
| cratio6 | .0398 |
|---|
| lratio1 | .0859 |
|---|
| lratio2 | .1420 |
|---|
| lratio3 | .6366 |
|---|
| lratio4 | .2865 |
|---|
| lratio5 | .2344 |
|---|
| lratio6 | .1157 |
|---|