How to Find the Port Size for a Sub Box
- 1). Visit one of the three online port tube length formula calculators in the References section. These calculators will help you find the appropriate length for your port tube based on the size of your enclosure and the diameter of your port hole. Fill in the required information in one of the sites, and calculate your port length. This is the number of inches that you need to cut your port tube down to.
- 2). Measure your port tube, and mark the point at which you need to cut it.
- 3). Cut the port tube down to size using your chop saw. The tube can now be installed and will be the optimal length to work with your speaker enclosure.
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