Box Parameters Audiobahn Box Specifications All ports listed are circle ports unless otherwise stated. Surface area of a circle port = (3.14) X (radius) (squared) Remember to build your box to the total volume, not just air space, as total volume includes all displacement. Model # AW831T AW1051T AW1251T AW1571T 0.7 2 x 6.1 12.77 36 40 0.08 0.009 0.75 0.65 2 x 6.5 33.45 40 40 0.1 0.01 0.75 1.3 3 x 6.75 27.15 44 40 0.15 0.024 1.5 1.7 3x7 28.15 40 35 0.21 0.025 2 Ported Air Space (Cu. Ft.