One of the things I needed in order to build my Adire Alignment sub was Polyfill, 64 ounces of it. I found some at a local craft store, sold in numerous sized bags. I ended up with 68 ounces of it. I was planning on just putting it all in the cabinet, then I remembered my friend wanted to stuff his PB-12. I told him he would not notice a difference in such a small cabinet. Im I right? I thought 4 ounces would fit nice inside his Pb-12 but would it yield a noticable improvment?