Is this correct? Subwoofer Enclosure Calculators, Parallel, Series, Port Length and Volume (the12volt.com) Go to Slot Port Length Calculator. Port width 20" x Port height 3" x Box volume 6.5ft x Tuning frequency 30hz = 21" for the length of the port. Is this the correct length of the port for a 30hz tune? Please let me know if this calculator is right or not? Thank you for your time!
