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Syncal1
06-04-2009, 02:40 PM
Good morning. I wood like to ask a question. I have an L7 dual 2 ohm voice coil 12 in my boat. I have it in a sealed 1.5 cubic foot enclosure with out the driver. I have it wired at 1 ohm to a crossfire bmf 1000d also at 1 ohm.
It sounds great and is very accurate. I would like to get a little more output from the woofer. I was thinking of constructing a new ported enclosure to gain the desired output I'm looking for.
My question is pertain to the port. I've been researching my question and can't find the answer I'm looking for. I'm sorry to take up your time with this question. I just can't find anyone who is willing to guide my in the right direction.
I enjoy the accuracy of the driver in a sealed enclosure and would like to maintain that as much as I could. I'm confused as to tuning the enclosure to maintain the sound quality and reach the extra output I'm desiring.
Is there a formula that will allow the driver to perform in a larger scale of frequencies say 30-80hz opposed to say 38hz? Also if I tune the enclosure to say 38hz will it only perform well at frequency?
Could you please send me a link that explains how to achieve this if it's possible in non engineer terminology lol. I'm truly sorry for the length of the question. I'm trying to learn as much as I can so I don't have to bother any one.
Thank you for you time have a good day.
Anthony

93dakota
06-04-2009, 04:49 PM
The tuning of a port does not mean that it will only preform well at that frequency. It will how ever have the output peak at that frequency as well as will not allow the sub to take much power under that frequency with out bottoming out the sub(typically doesn't happen unless you are playing 10-20 Hz below tuning). But is you tune an enclosure right they can sound very good. If you are looking to have and enclosure that peaks at more frequencies then you many want an enclosure with a folding horn. I don't know much about them but i hear they sound good. Here is a web site with some tutorials

http://mobile.jlaudio.com/support_pages.php?page_id=141

Supergumby5000
06-04-2009, 04:53 PM
The tuning of a port does not mean that it will only preform well at that frequency. It will how ever have the output peak at that frequency as well as will not allow the sub to take much power under that frequency with out bottoming out the sub(typically doesn't happen unless you are playing 10-20 Hz below tuning). But is you tune an enclosure right they can sound very good. If you are looking to have and enclosure that peaks at more frequencies then you many want an enclosure with a folding horn. I don't know much about them but i hear they sound good. Here is a web site with some tutorials

http://mobile.jlaudio.com/support_pages.php?page_id=141

i'll have to disagree with this bit.

Mathematically, you will peak at the tuning frequency, but in a real world environment you will not peak at this frequency. If you want ot get real technical, download WinISD (free), plug in your subwoofer parameters, and model the response curve of the driver to have a flat response for as long and low as possible.

If you dont want to do that approach, a safe bet is to usually use a large box with low tuning. This lets the range of the subs playable frequencies to increase, but at the risk of having a loss of output due to not directly pairing the parameters of the driver to the subwoofer enclosure.

Syncal1
06-04-2009, 06:49 PM
Thank you both for the reply. They both were very helpful.

7ender
06-05-2009, 01:07 AM
Just out of curiousity, what kind of boat?