I have built many speakerboxes. they have been ported and tuned to 35 hz. however, someone told me the other day that if you put insulation in the box it puts out a deeper thump. is this true? and if so, where do you put the insulation? (obviously inside the box, but is it around the sides?) also, what is the effect of the sound if you flip the subs so the magnet is outside of the box and the face of the cone is inside?
idk about the insulation.. i dont think it would change sound in a ported box.. however, reverse mounting your subs may SLIGHTLY change sound because you will have more volume inside your box, due to not having 2 bulky beasts nestling in it... haha
thanks. i am building a fully customized box for a friend of mine. he's got an 09 hyundai elantra and i am converting his whole trunk and turning it into a huge speakerbox. its going to be beastly.
Pretty much covers it. Also if you're worried about inverting your subs and affecting your tuning you can always add ballast to the inside of the box equal to the sub's displacement. Simply glue a 2 X 4 of the appropriate length to the inside. Problem solved. If you're custom building the box then simply omit the displacement in your calcs. What sux about inverting though is you reduce the amount of space you have outside the box. Plus it exposes all the moving parts to dust and any possible interaction with anything else you have floating around in the trunk. And inverting has NO affect on SQ or SPL. It's a driver moving in two directions. It doesn't care which side of the baffle its' on.
plus in most cases you get motor noise when they are inverted.
Polyfill make your sub act like it is in a larger inclosure. Although everhyoned that I know who has tried it, including myself, have noticed no audible diffeerence.
Thank you all for the help. I drafted out the box to specs based off of the manufacturer. They recommend 2 cu ft per chamber per sub. should i use polyfill if i have it designed to have 2 cu ft already?
We have done their 1.4 box boosted to 2.00 after fiberfill and it did change the tuning just like his example shows. Another great thing that comes out of this is you have a 2.0 box with a 1.4 size....a big savings in space plus it increases sound quality by having the fill in there. Definitely valuable things for a small investment to me. The difference is learning and planning to put it to use. You can even make a box thats to big smaller with fill if you put to much in which is also good sometimes. It beats building a new box.