posted
Right now I have 4 ports in my box measureing 4"dia X 14"long each. I was wandering if it would be better to put in vents instead, and what the measurements would be for an equal vent?
posted
The last time I checked, ports were vents. I think you mean rectangular ports??? Well, the advantage you get with rectangular ports is that you can get more port area out of an enclosure, and you can build it right into the box out of MDF instead of using tubing. I prefer rectangular in my enclosures...
------------------ Adam Basalyga Ultimate Audio "The Science Of Car Audio!"
posted
OK... I think it's radius X Pi( 2.14 ) X number of ports= 68.48 inches. I could be wrong and probably am, I should've took more math in H.S. =) Wait until someone can verify this. =) As far as getting the measurements for a rect. vent, it's ( L X W )or( W X H )=port area in square inches). Ie...6"wide X 12.75height=76.5 square inches. =)
------------------ SS3-4 1600watts to the highs and 4000 watts to the subs...opps..( currently rebuilding ) I mean 16000 watts to the subs. =)
Posts: 842 | From: Milwaukee, WI USA | Registered: Feb 2001
| IP: Logged |
posted
the area of a circle is pi times radius^2...and pi is approx 3.14 so if you had 1 4" port, you would do the following... 4/2=2 (2 is the radius) sqaure the radius then multiply by pi 3.14*2^2=12.56 in^2 if you wanted the volume, you just take the square inches and multiply by the length of the port and you then have cubic inches (in^3) area of a rectangular port is just simply length times width hope this cleared up the math before someone started using wrong numbers hehe
------------------
Posts: 50 | From: Louisville, KY USA | Registered: Mar 2001
| IP: Logged |
posted
Not quite. Check out www.jlaudio.com in the tutorials section and it goes through the right method. The above method is about 10% out in some cases due to frictional losses at the port wall being reduced when going from 4 4" ports to one big slot port, o the length needs to be adjusted as well to maintain the same tuning. Colin
------------------ Warning SPL in my car exceeds government health guidelines, civilians are advised to proceed with caution. Failiure to comply may result in serious injury or death.
Printer-friendly view of this topic