15''Dual vented Sub Box----The box needs to be 49" Wide and 19" Tall.----- (2 chambers) ----- Air Volume 3.4 Cubic Feet Per Side.How long would the box have to be?-----?" L x 49" W x 19" H thanks mike}}}
Yes, I can. When I started designing enclosures, there was no internet, no computer calculators to do the work, and no modeling software. The point is, however, that you didn't even know the formula for the volume of a box! That's kind of sad, you have to admit. I mean come on.. this is junior high school algebra.
are you venting both the front and rear chambers of the box? a 3rd order enclosure would have one chamber sealed. What are you aiming for here?