Building sub enclosure. Volume on Adire plans not matching up

Damn Darren, emailed me, so I had to actually do the calculations, or maybe I didn't, oh well did them anyways :p)

Here is my email reply to Darren for those lurkers who might want to read it:

Well I punched the numbers through. I came up with 13448"^3 for the gross. And 1080"^3 for the driver, ports and braces. Which gives a net of 12368"^3. Which is 202.8L.

The plans also call for 64 ounces of polyfill. When you add polyfill or a similar material to an enclosure, its' appearant volume increases. So in reality the enclosure will be seen as effectively 214L to the driver and ports (Adire likely measured the tune from a finished sub, and figured out how much the polyfill increased the appearant volume and quoted that for the enclosure).

The other thing to remember is at this size, being up or down 10L doesn't really affect anything. The tune may go up 1/2 a hz or down 1/2hz. But with two enclosures side by side that differed like this you couldn't tell the difference.

My sub is 260L and tuned to somewhere between 15.75 and 16.75hz with a 6" port. What the appearant volume is from the little bit of insulation and polyfill in my sub is I don't know. Doesn't really matter to me either, sounds great.