port frequency

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=29409
Printed Date: July 24, 2025 at 10:07 PM

Topic: port frequency

Posted By: flatulatta
Subject: port frequency
Date Posted: March 31, 2004 at 2:25 PM

what is the "best" frequency for a daily driver or can someone point me in the range of a good freq?? i have a L712 and wanna port it but i wanna keep it sounding as good as possible...any suggestions

Replies:

Posted By: t_808
Date Posted: April 01, 2004 at 3:49 PM

There isnt really a best frequency, in most speaker boxes you have a rise in frequency response on the low end. what you want to do with porting is to allow the port to dampen the speaker at this rise (which is usually what causes boominess) in frequency response.By properly tuning your box it dampens the speaker which helps to extend the frequency response.Generally when you port the box properly it will dampen at the resonance of the box and instead of having one large rise in response you will have two smaller rises on either side of the resonace frequencywhich is how it extends bass response.Of course the acoustics of the car will also dictate the frequency response of the box.

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t-win

Posted By: flatulatta
Date Posted: April 01, 2004 at 3:53 PM

i dont think ican port it .... b/c i dont have a subsonic filter... : (

Posted By: DYohn
Date Posted: April 01, 2004 at 4:08 PM

flatulatta wrote:

i dont think ican port it .... b/c i dont have a subsonic filter... : (

Huh? One has nothing to do with the other, flatulatta. What made you think this?

Posted By: flatulatta
Date Posted: April 01, 2004 at 7:22 PM

well... in my book form kicker it says not to port a box unless you have a subsonic filter on your amp and i dont have one.......so i thought i couldnt port or if i did it would damage the sub......bye L712

Posted By: DYohn
Date Posted: April 01, 2004 at 8:01 PM

That's a new one on me. Probably because Kicker has over-rated the sub so they want to make sure it can handle something close to the wattage they specify and they know it cannot handle very low frequency excursions. Subsonic filters on amps have nothing to do with whether to port or not. SPL vs SQ does.

Posted By: flatulatta
Date Posted: April 01, 2004 at 8:09 PM

ahh.... ok.... lol iknow mine can tak like 30hz... so..... how do i go about porting..whats the best thing 2 use?? PVC??

Posted By: DYohn
Date Posted: April 01, 2004 at 8:13 PM

The best thing to use (and the easiest) are pre-made ports like these (there are three pages of ports here.): https://www.partsexpress.com/webpage.cfm?webpage_id=3&SO=2&&DID=7&CAtid=48&ObjectGroup_ID=143

Posted By: stevdart
Date Posted: April 01, 2004 at 10:25 PM

I show this calculator https://www.bcae1.com/spboxad2.htm often because it's easy to use. It will help a lot when you're figuring box size. Scroll past the graphs to get to it.