56 pages

Subwoofer Port Length by Box Volume and Tuning Frequency

Pick the net volume of your box and the frequency you want to tune it to. Each page gives the length for every sensible round and slot port, the port area the convention asks for, and the reason a larger port is always a much longer one.

• 1 cu ft at 28 Hz A 4 inch round port tuning 1 cubic feet to 28 Hz needs 41.55 inches. Round and slot port lengths, port area and the Helmholtz rela
• 1 cu ft at 30 Hz A 4 inch round port tuning 1 cubic feet to 30 Hz needs 35.98 inches. Round and slot port lengths, port area and the Helmholtz rela
• 1 cu ft at 32 Hz A 4 inch round port tuning 1 cubic feet to 32 Hz needs 31.43 inches. Round and slot port lengths, port area and the Helmholtz rela
• 1 cu ft at 33 Hz A 4 inch round port tuning 1 cubic feet to 33 Hz needs 29.45 inches. Round and slot port lengths, port area and the Helmholtz rela
• 1 cu ft at 35 Hz A 4 inch round port tuning 1 cubic feet to 35 Hz needs 26 inches. Round and slot port lengths, port area and the Helmholtz relatio
• 1 cu ft at 37 Hz A 4 inch round port tuning 1 cubic feet to 37 Hz needs 23.09 inches. Round and slot port lengths, port area and the Helmholtz rela
• 1 cu ft at 40 Hz A 4 inch round port tuning 1 cubic feet to 40 Hz needs 19.52 inches. Round and slot port lengths, port area and the Helmholtz rela
• 1 cu ft at 42 Hz A 4 inch round port tuning 1 cubic feet to 42 Hz needs 17.55 inches. Round and slot port lengths, port area and the Helmholtz rela
• 1.25 cu ft at 28 Hz A 4 inch round port tuning 1.25 cubic feet to 28 Hz needs 32.91 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.25 cu ft at 30 Hz A 4 inch round port tuning 1.25 cubic feet to 30 Hz needs 28.46 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.25 cu ft at 32 Hz A 4 inch round port tuning 1.25 cubic feet to 32 Hz needs 24.81 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.25 cu ft at 33 Hz A 4 inch round port tuning 1.25 cubic feet to 33 Hz needs 23.23 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.25 cu ft at 35 Hz A 4 inch round port tuning 1.25 cubic feet to 35 Hz needs 20.47 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.25 cu ft at 37 Hz A 4 inch round port tuning 1.25 cubic feet to 37 Hz needs 18.14 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.25 cu ft at 40 Hz A 4 inch round port tuning 1.25 cubic feet to 40 Hz needs 15.29 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.25 cu ft at 42 Hz A 4 inch round port tuning 1.25 cubic feet to 42 Hz needs 13.71 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.5 cu ft at 28 Hz A 4 inch round port tuning 1.5 cubic feet to 28 Hz needs 27.15 inches. Round and slot port lengths, port area and the Helmholtz re
• 1.5 cu ft at 30 Hz A 4 inch round port tuning 1.5 cubic feet to 30 Hz needs 23.44 inches. Round and slot port lengths, port area and the Helmholtz re
• 1.5 cu ft at 32 Hz A 4 inch round port tuning 1.5 cubic feet to 32 Hz needs 20.4 inches. Round and slot port lengths, port area and the Helmholtz rel
• 1.5 cu ft at 33 Hz A 4 inch round port tuning 1.5 cubic feet to 33 Hz needs 19.09 inches. Round and slot port lengths, port area and the Helmholtz re
• 1.5 cu ft at 35 Hz A 4 inch round port tuning 1.5 cubic feet to 35 Hz needs 16.78 inches. Round and slot port lengths, port area and the Helmholtz re
• 1.5 cu ft at 37 Hz A 4 inch round port tuning 1.5 cubic feet to 37 Hz needs 14.85 inches. Round and slot port lengths, port area and the Helmholtz re
• 1.5 cu ft at 40 Hz A 4 inch round port tuning 1.5 cubic feet to 40 Hz needs 12.46 inches. Round and slot port lengths, port area and the Helmholtz re
• 1.5 cu ft at 42 Hz A 4 inch round port tuning 1.5 cubic feet to 42 Hz needs 11.15 inches. Round and slot port lengths, port area and the Helmholtz re
• 1.75 cu ft at 28 Hz A 4 inch round port tuning 1.75 cubic feet to 28 Hz needs 23.04 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.75 cu ft at 30 Hz A 4 inch round port tuning 1.75 cubic feet to 30 Hz needs 19.86 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.75 cu ft at 32 Hz A 4 inch round port tuning 1.75 cubic feet to 32 Hz needs 17.25 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.75 cu ft at 33 Hz A 4 inch round port tuning 1.75 cubic feet to 33 Hz needs 16.12 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.75 cu ft at 35 Hz A 4 inch round port tuning 1.75 cubic feet to 35 Hz needs 14.15 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.75 cu ft at 37 Hz A 4 inch round port tuning 1.75 cubic feet to 37 Hz needs 12.49 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.75 cu ft at 40 Hz A 4 inch round port tuning 1.75 cubic feet to 40 Hz needs 10.45 inches. Round and slot port lengths, port area and the Helmholtz r
• 1.75 cu ft at 42 Hz A 4 inch round port tuning 1.75 cubic feet to 42 Hz needs 9.32 inches. Round and slot port lengths, port area and the Helmholtz re
• 2 cu ft at 28 Hz A 4 inch round port tuning 2 cubic feet to 28 Hz needs 19.95 inches. Round and slot port lengths, port area and the Helmholtz rela
• 2 cu ft at 30 Hz A 4 inch round port tuning 2 cubic feet to 30 Hz needs 17.17 inches. Round and slot port lengths, port area and the Helmholtz rela
• 2 cu ft at 32 Hz A 4 inch round port tuning 2 cubic feet to 32 Hz needs 14.89 inches. Round and slot port lengths, port area and the Helmholtz rela
• 2 cu ft at 33 Hz A 4 inch round port tuning 2 cubic feet to 33 Hz needs 13.9 inches. Round and slot port lengths, port area and the Helmholtz relat
• 2 cu ft at 35 Hz A 4 inch round port tuning 2 cubic feet to 35 Hz needs 12.18 inches. Round and slot port lengths, port area and the Helmholtz rela
• 2 cu ft at 37 Hz A 4 inch round port tuning 2 cubic feet to 37 Hz needs 10.72 inches. Round and slot port lengths, port area and the Helmholtz rela
• 2 cu ft at 40 Hz A 4 inch round port tuning 2 cubic feet to 40 Hz needs 8.94 inches. Round and slot port lengths, port area and the Helmholtz relat
• 2 cu ft at 42 Hz A 4 inch round port tuning 2 cubic feet to 42 Hz needs 7.95 inches. Round and slot port lengths, port area and the Helmholtz relat
• 2.5 cu ft at 28 Hz A 4 inch round port tuning 2.5 cubic feet to 28 Hz needs 15.63 inches. Round and slot port lengths, port area and the Helmholtz re
• 2.5 cu ft at 30 Hz A 4 inch round port tuning 2.5 cubic feet to 30 Hz needs 13.41 inches. Round and slot port lengths, port area and the Helmholtz re
• 2.5 cu ft at 32 Hz A 4 inch round port tuning 2.5 cubic feet to 32 Hz needs 11.58 inches. Round and slot port lengths, port area and the Helmholtz re
• 2.5 cu ft at 33 Hz A 4 inch round port tuning 2.5 cubic feet to 33 Hz needs 10.79 inches. Round and slot port lengths, port area and the Helmholtz re
• 2.5 cu ft at 35 Hz A 4 inch round port tuning 2.5 cubic feet to 35 Hz needs 9.41 inches. Round and slot port lengths, port area and the Helmholtz rel
• 2.5 cu ft at 37 Hz A 4 inch round port tuning 2.5 cubic feet to 37 Hz needs 8.25 inches. Round and slot port lengths, port area and the Helmholtz rel
• 2.5 cu ft at 40 Hz A 4 inch round port tuning 2.5 cubic feet to 40 Hz needs 6.82 inches. Round and slot port lengths, port area and the Helmholtz rel
• 2.5 cu ft at 42 Hz A 4 inch round port tuning 2.5 cubic feet to 42 Hz needs 6.03 inches. Round and slot port lengths, port area and the Helmholtz rel
• 3 cu ft at 28 Hz A 4 inch round port tuning 3 cubic feet to 28 Hz needs 12.75 inches. Round and slot port lengths, port area and the Helmholtz rela
• 3 cu ft at 30 Hz A 4 inch round port tuning 3 cubic feet to 30 Hz needs 10.9 inches. Round and slot port lengths, port area and the Helmholtz relat
• 3 cu ft at 32 Hz A 4 inch round port tuning 3 cubic feet to 32 Hz needs 9.38 inches. Round and slot port lengths, port area and the Helmholtz relat
• 3 cu ft at 33 Hz A 4 inch round port tuning 3 cubic feet to 33 Hz needs 8.72 inches. Round and slot port lengths, port area and the Helmholtz relat
• 3 cu ft at 35 Hz A 4 inch round port tuning 3 cubic feet to 35 Hz needs 7.57 inches. Round and slot port lengths, port area and the Helmholtz relat
• 3 cu ft at 37 Hz A 4 inch round port tuning 3 cubic feet to 37 Hz needs 6.6 inches. Round and slot port lengths, port area and the Helmholtz relati
• 3 cu ft at 40 Hz A 4 inch round port tuning 3 cubic feet to 40 Hz needs 5.41 inches. Round and slot port lengths, port area and the Helmholtz relat
• 3 cu ft at 42 Hz A 4 inch round port tuning 3 cubic feet to 42 Hz needs 4.75 inches. Round and slot port lengths, port area and the Helmholtz relat