If you need a 16 mHy coil, you can series a 12.8 mHy coil and a 3.2 mHy coil. If you need a 70 µfd capacitor, you can parallel two 35 µfd capacitors.When the exact value of a coil or capacitor is not available, you can substitute values of ± 5% . To get the needed values for desired crossover frequencies not listed, use these formulas & calculators.

High Pass, Low Pass, Band Pass

Narrow Band Pass

Low Pass, High Pass, Band Pass for 4 Ohm Load
Capacitor (C) values = microfarads (µfd) Coil (L) values = millihenries (mHy)
Crossover Frequency		1st Order 6 dB			2nd Order 12 dB			3rd Order 18 dB
(Hz)		L1	C1		L2	C2		L3	C3	L4	C4	L5	C5
50 60 70 75 80 85 100 120 125 150 200 250 275 300 400 500 600 800 1000 2000 2500 3000 3500 4000 5000 6000 7000 8000 9000 10,000		12.7 10.6 9.1 8.5 7.9 7.5 6.3 5.3 5.1 4.2 3.18 2.55 2.32 2.12 1.59 1.27 1.06 .79 .64 .32 .25 .21 .18 .16 .13 .11 .09 .08 .07 .06	796 663 568 531 497 468 398 331 318 265 199 159 145 133 99 80 66 50 40 20 16 13 11 9.9 8.0 6.6 5.7 4.9 4.4 4.0		18.0 15.0 12.8 11.9 11.3 10.6 9.0 7.5 7.2 6.0 4.5 3.6 3.27 3.00 2.25 1.80 1.50 1.13 .90 .45 .36 .30 .26 .23 .18 .15 .13 .11 .10 .09	563 468 401 375 352 331 281 234 225 188 141 113 102 94 70 56 47 35 28 14 11 9.4 8.0 7.0 5.6 4.7 4.0 3.5 3.1 2.8		19.1 15.9 13.6 12.7 12.0 11.0 9.6 7.9 7.6 6.4 4.8 3.8 3.5 3.2 2.4 1.9 1.6 1.2 .95 .48 .38 .32 .27 .24 .19 .16 .14 .12 .11 .10	1058 882 756 706 662 623 529 441 423 353 265 212 192 176 132 106 88 66 53 26 21 18 15 13 11 8.8 7.6 6.6 5.9 5.3	6.37 5.31 4.54 4.24 3.97 3.74 3.18 2.65 2.55 2.12 1.59 1.27 1.12 1.06 .79 .64 .53 .39 .32 .16 .13 .11 .09 .08 .06 .05 .05 .04 .04 .03	530 442 379 354 331 312 265 221 212 177 133 106 97 89 66 53 44 33 27 13 11 8.8 7.6 6.6 5.3 4.4 3.8 3.3 2.9 2.7	9.5 7.9 6.8 6.4 5.9 5.6 4.8 3.9 3.8 3.2 2.4 1.9 1.7 1.6 1.2 .95 .79 .59 .48 .24 .19 .16 .14 .12 .10 .08 .07 .06 .05 .05	1592 1326 1137 1061 995 936 796 663 637 531 398 318 289 265 199 159 133 99 80 40 32 27 23 20 16 13 11 9.9 8.8 7.9
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Narrow Band Pass for 4 Ohm Load - Mid-Bass Loudspeakers
Capacitor (C) values = microfarads (µfd) Coil (L) values = millihenries (mHy)
Frequency Bandwidth		1st Order 6 dB			2nd Order 12 dB					3rd Order 18 dB
(Hz)		C1	L1		C1	L1	C2	L2		C1	L1	C2	L2	C3	L3
60 - 200  60 - 300  70 - 200  70 - 300  70 - 400  80 - 200  80 - 300  80 - 400  85 - 200  85 - 300  85 - 400 100 - 250 100 - 300 100 - 400 100 - 500		464 530 370 436 468 298 365 398 269 336 369 239 265 298 318	4.55 2.65 4.90 2.77 1.93 5.31 2.89 1.99 5.56 2.96 2.10 4.24 3.18 2.12 1.59		201 117 216 122 85 234 128 88 245 131 89 188 141 94 70	10.5 12.0 8.36 9.86 10.6 6.75 8.26 9.01 6.09 7.59 8.34 5.40 6.00 6.75 7.20	328 375 261 308 331 211 258 281 190 237 261 169 188 211 225	6.43 3.75 6.93 3.92 2.73 7.50 4.09 2.81 7.83 4.20 2.86 6.00 4.50 3.00 2.25		312 356 248 293 315 200 245 267 181 225 248 160 178 199 214	6.77 3.95 7.29 4.12 2.87 7.89 4.31 2.96 8.24 4.41 3.01 6.32 4.74 3.16 2.37	382 223 411 232 162 446 243 167 468 249 170 356 267 178 133	5.53 6.34 4.39 5.19 5.58 3.55 4.34 4.74 3.21 3.99 4.39 2.84 3.16 3.55 3.79	929 1061 739 872 938 597 730 796 538 671 737 478 531 597 637	2.27 1.33 2.45 1.38 0.96 2.65 1.50 0.99 2.77 1.48 1.01 2.12 1.59 1.06 0.79
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Passive Crossovers		Car Audio
First Order Filters Second Order Filters Third Order Filters Formulas & Calculators	2 Ohm Charts 4 Ohm Charts 8 Ohm Charts	Glossary Installs Ohm's Law Passive Crossovers Power and Ground Cable Sizes Subwoofer Enclosures the12volt's Install Bay Tools & Equipment