Advice on my sub boxes please

thrower78

A big hello to all from Australia,

I have been having little success finding info on polk subs and boxes over here as they are only starting to flow into our popular market.

I am building some boxes for my 2 db1040svc subs (2 single boxes). I am using 1 inch mdf and have got my internal box volume to almost exactly what it specifies on the polk box plan page. A side question here is I assume that the volume of .66cu. ft. or 18.69L is the internal volume once the woofer is in place, ie. total box volume - volume of the woofer cone/magnet takes up?

I am going to talk in litres here for a little bit (sorry). Because when you work out the straight volume off the dimensions on the polk site for the db1040 sealed box using 19mm mdf it is 23.76L which must be 18.69 once you take woofer volume away? I have got the dimensions of my box to equal 23.56L so pretty much the same.

Now to my main question. On the polk site it states "minimal polyfil" on the box design page for this particular box. How much does this mean? How much should I put in? should it sit loose in the bottom of glued to the back and sides? Has anyone else built these particular boxes did you use it did it make a difference.

I don't particually want to be taking the woofer in and out heaps of times seeing if the polyfil makes a difference. Hopefully someone here can shed some light on the issue.

Thanks in Advance
Andrew

thrower78

Anyone got ideas on how much minimal polyfil means? Surley there are people on here that have built boxes for db 10" subs and know how much polyfil works best? Any ideas

Thanks Andrew

MCCLIPSE

I just installed my MM 8" sub Monday and I just shoved the box as full as it can go with polyfill and it sounds great. I might be wrong, but I don't think too much of it hurts your sound at all. I've always been told the more you have in there, the cleaner your bass will be. One of the main purposes of polyfill is to fool the sub into thinking it's in a bigger box. When you have constraints on space and you can't get your box to be quite big enough for the minimum airspace the sub requires, the polyfill corrects this a little bit so you can get away with it.

thrower78

If thats the case then that is easy. I was just worried there might have been a finite measure, but if it just a matter of filling the box reasonably full then that is easy.

Andrew