So I Just Bought 4 Nightshade 18s And I Was Wondering What Would Be A Good Box Size To Use Im Thinking 19.5 Cubes With 4 6 Inch Aeros Tuned To 27 16 Cube After Displacemnt And Bracing Made From Birch With 2 Saz4500ds At .5 On 8 16vs And 4 270amp Alts