# Subwoofer Enclosure Calculators - Fraction to Decimal, Parallel, Series, Port Length, & Volume

To calculate interior volume, first convert all fractions to decimals (½ = .5) before entering the width, height, depth, or diameter, and thickness into any of our speaker box calculators below.

 Fraction to Decimal Calculator In the fraction ½, 1 is the numerator and 2 is the denominator. Numerator Decimal Denominator
Parallel Calculator
Enter at least 2 values and up to 10 values to calculate the resistance of speakers or voice coils connected in parallel. R = Resistance in Ohms.
R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R Total
ohms ohms ohms ohms ohms ohms ohms ohms ohms ohms ohms
Series Calculator
Enter at least 2 values and up to 10 values to calculate the resistance of speakers or voice coils connected in series. R = Resistance in Ohms.
R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R Total
ohms ohms ohms ohms ohms ohms ohms ohms ohms ohms ohms

 Round Port Length Calculator To calculate the port length of a round port, enter the diameter of the port (D), the box volume (Vb) in cubic feet, and the desired tuning frequency (Fb). Here is the formula we use: ((14630000*(D/2)*(D/2))/((Fb*Fb*Vb*1728)-(1463*(D/2)))) Please compare your answers with other programs that include other allowances such as tapered ports. Port Diameter (D) Box Volume (Vb) Tuning Frequency (Fb) Port Length inches cubic feet hertz inches
 Slot Port Length Calculator To calculate the port length of a slot port, enter the width and height of the port, the box volume (Vb) in cubic feet, and the desired tuning frequency (Fb). Port Width Port Height Box Volume (Vb) Tuning Frequency (Fb) Port Length inches inches cubic feet hertz inches
 Volume Calculator - Rectangular/Square Enclosures Measure the outside dimensions of your enclosure and the material thickness, then enter the numbers below to calculate interior volume. **Note: If you used dividers and/or braces, the volume of each divider/brace will need to be subtracted from the interior volume. Width Height Depth Thickness Interior Volume inches inches inches inches cubic feet
 Volume Calculator - Wedge Enclosures 1 Measure the outside dimensions of your enclosure and the material thickness, then enter the numbers below to calculate interior volume. **Note: If you used dividers and/or braces, the volume of each divider/brace will need to be subtracted from the interior volume. Width Height Depth Thickness Interior Volume inches inches inches inches cubic feet
 Volume Calculator - Wedge Enclosures 2 Measure the outside dimensions of your enclosure and the material thickness, then enter the numbers below to calculate interior volume. **Note: If you used dividers and/or braces, the volume of each divider/brace will need to be subtracted from the interior volume. Width Height 1 Height 2 Depth Thickness Interior Volume inches inches inches inches inches cubic feet
 Volume Calculator - Tube/Cylinder Enclosures Measure the outside dimensions of your enclosure and the material thickness, then enter the numbers below to calculate interior volume. **Note: If you used dividers and/or braces, the volume of each divider/brace will need to be subtracted from the interior volume. Diameter Height Thickness Interior Volume inches inches inches cubic feet

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