Enter the number of ports, vent diameter, box volume, and tuning frequency into the calculator to determine the port length.

Port Length Formula

The following is the port length formula:

L = [ ( 2.356*10^4* D^2*N)/(V*F^2) ] * (k*D)
  • Where L is the port length
  • D is the vent diameter
  • N is the total number of ports
  • V is the volume of the box
  • F is the tubing frequency
  • k is the correction factor (.732)

Port Length Definition

A port length is defined as the proper length of the vent of a subwoofer.

How to calculate a port length?

  1. First, determine the vent diameter.
  2. Next, determine the total number of ports.
  3. Next, determine the volume of the box housing.
  4. Next, determine the tubing frequency.
  5. Finally, calculate the port length using the formula above.
port length calculator
port length formula