l200/5foot enclosure vents
Thanks Tom, I calculated a little over 6 cubic feet but that was based on external published dimensions and I knew that couldnt be right.
Mr. Widget, what about using three ports in a five cubic feet enclosure, could I decrease the length of the vents, (like in my 4518 enclosure for my 2245h). I dont have box modeling software, but planned on trying the sub1500 in these L200 enclosures this weekend and thought I could throw another vent into the horn hole. I think the vents in the L200 are three inches, I could install three four inch ones, but dont know what depth. (obviously I would prefer to just have three of the ones in place but would probably have 24 inch port tubes).
Thanks, my wife is extremely excited about getting the pair of SUB1500s, and my brand new used Crown K2 pounding in our 150 ft2 living room :duck: ,
Oh well, its either speakers or the AV room addition, I dont have time for everything :thnkfast:
Re: l200/5foot enclosure vents
Quote:
Originally posted by andresohc
Mr. Widget, what about using three ports in a five cubic feet enclosure, could I decrease the length of the vents, (like in my 4518 enclosure for my 2245h).
Essentially as the area of the port increases the port length must increase to maintain the same tuning frequency. So if you use (1) 4" tube for 21Hz it is 11.3", (2) 4" tubes for 21Hz are each 26", (3) 4" tubes for 21Hz are each 41".
Now a hole cut into a 1" baffle with no tube would be a little under 1.75" in diameter. The problem with the smaller port diameters is that as they get smaller the likelihood of air moving through the port causing audible noise goes up.
Since JBL typically tunes in the 30Hz up range the ports are shorter in length.
Widget