jarod027 Posted May 6, 2010 Author Report Share Posted May 6, 2010 That rule is mostly for slot ports, aeroport are more efficient, a round port needs about 9-13 SQ of port per cubic feet, said that, that´s why i would use minimun 3 4" ports, besides that, where do you get 56 SQ of port with a single 4" tube????? pi x ®2 3.1416 x (2)2 3.1416 x 4 = 12.57 square inches!! 3 4" ports would be 37 square inches Simple basic maths... because the tube is 4.5" long as well. Quote Link to comment Share on other sites More sharing options...
bkolfo4 Posted May 6, 2010 Report Share Posted May 6, 2010 because the tube is 4.5" long as well. Which would be volume, not area. . . we are looking at sq-in, not cu-in. Quote Current system: 1997 Blazer - (4) Customer Fi NEO subs with (8) American Bass Elite 2800.1s Previous systems: 2000 Suburban - (4) BTL 15's and (4) IA 40.1's = 157.7 dB at 37 Hz. 1992 Astro Van - (6) BTL 15's and (6) IA 40.1's = 159.7 dB at 43 Hz. Link to comment Share on other sites More sharing options...
jarod027 Posted May 6, 2010 Author Report Share Posted May 6, 2010 Which would be volume, not area. . . we are looking at sq-in, not cu-in. Oh, alright I understand. confusion on my part. So, if i'm going with that many ports, how do I get a frequency as low as 30? Quote Link to comment Share on other sites More sharing options...
fecupe2001 Posted May 6, 2010 Report Share Posted May 6, 2010 Actually my friend, it does not. . .but it is a nice approximation for those that cannot figure out how much port area they really need. . . As i said before, for people that not care on competing or looking for the maximun efficiency on a box, port area depends on a lot of factors including power, but once again, for people that don´t know and don´t care really, port area depends mostly on the box size and power... Quote I´m the SPL Gains topic creator!! wanna get louder?? check this: SPL Gains. Panamenian 2009 & 2010 & 2014 Bass Race 149.9 Champion! 2 15" subs and a 2K wired at 1 ohm, http://www.stevemeadedesigns.com/board/topic/167788-fecupe2001-2-15s-on-a-2k-video-on-page-3/ 8 Massive 15" subs and small power, http://www.stevemeadedesigns.com/board/topic/179296-fecupe2001s-8-15s-4th-order-bandpass-wall/ Link to comment Share on other sites More sharing options...
jarod027 Posted May 6, 2010 Author Report Share Posted May 6, 2010 So, for a box this size, do you guys recommend doing slotted ports rather than round? Quote Link to comment Share on other sites More sharing options...
vee333gp Posted May 6, 2010 Report Share Posted May 6, 2010 fecupe i agree port area works with power and volume so what power u using to drive woofers Quote Link to comment Share on other sites More sharing options...
jarod027 Posted May 6, 2010 Author Report Share Posted May 6, 2010 fecupe i agree port area works with power and volume so what power u using to drive woofers audioque1200d Quote Link to comment Share on other sites More sharing options...
fecupe2001 Posted May 6, 2010 Report Share Posted May 6, 2010 So, for a box this size, do you guys recommend doing slotted ports rather than round? Well, they both are nice, since you are not looking for score and you don´t care about testing wich one works best on your car, AERO FTW!! They take less internal space, easier to retune and test, you can use cheap PVC tubes and they need less area most of the time. fecupe i agree port area works with power and volume so what power u using to drive woofers Well, generally, the more power you have the more port you can get, this also depends on the car, my little swift HATES big ports and big subs, works great with 10´s and 12´s , bigger than that, scores the same or maybe less. My explorer likes much bigger port, said that: i have 16 SQ of port per cubic feet on the swift and worked awesome with my 6K amplifier, it broke down so now i have a 2K amplifier and still sounds loud, but i know it could be a lot louder with a smaller port, i don´t have the power for that port. The explorer has 20 SQ per cubic feet because i´m gonna use a 8K amplifier wich i haven´t bought yet, but with barely 3K watts it´s hitting around 151 right now, i´m just dreaming on a high 52 with my new amp, we´ll see... Quote I´m the SPL Gains topic creator!! wanna get louder?? check this: SPL Gains. Panamenian 2009 & 2010 & 2014 Bass Race 149.9 Champion! 2 15" subs and a 2K wired at 1 ohm, http://www.stevemeadedesigns.com/board/topic/167788-fecupe2001-2-15s-on-a-2k-video-on-page-3/ 8 Massive 15" subs and small power, http://www.stevemeadedesigns.com/board/topic/179296-fecupe2001s-8-15s-4th-order-bandpass-wall/ Link to comment Share on other sites More sharing options...
jarod027 Posted May 6, 2010 Author Report Share Posted May 6, 2010 So how many square inches of port do i need for aero? Quote Link to comment Share on other sites More sharing options...
bkolfo4 Posted May 6, 2010 Report Share Posted May 6, 2010 but once again, for people that don´t know and don´t care really, port area depends mostly on the box size and power... But that is not correct. . .It does not depend on box size at all. Those are just approximations so people are not constantly asking how much port area they need, since the true mount of port area required for a port to operate correctly without compression is almost never achieved in a vehicle. If I have a BTL 18 on 4000 watts tuned to 35 Hz in 6 cuft vs 10 cuft, I do not need a different size port. If I have a BTL 18 on 2000 watts vs 4000 watts in the same 10 cuft, they do not require the same amount of port area. Port size is correctly determined by cone displacement and tuning frequency. . . Quote Current system: 1997 Blazer - (4) Customer Fi NEO subs with (8) American Bass Elite 2800.1s Previous systems: 2000 Suburban - (4) BTL 15's and (4) IA 40.1's = 157.7 dB at 37 Hz. 1992 Astro Van - (6) BTL 15's and (6) IA 40.1's = 159.7 dB at 43 Hz. Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.