Pillow Stuffing in Box, Myth or Fact?

If your ported just use the sheet batting and spray adhere it to the inner walls of the box. Sealed boxes, use the bulk fill and try not to let it plug any vents around the driver.This is what I do for FUN!

there are some pretty cheap options i buy a sound deadening material from jaycar at like $10 a bag which is enough for a box where my pillows cost like $50 :) it does give a better sound noticebly in the boxes ive built. im not entirely sure about the technical aspects but ive been told it makes the box appear bigger to the sound waves and removes/reduces any extra beats being produced by the backwards travel of the sub which gives you a nice tight sound. so it may not be ideal if you have cheap 15" subs and listen to hiphop :)