15" brahma...entering comp, need help

[audio hoe 10+ year member]

what would you recomend for box size and tuned to what freq. for the brahma to play the loudest possible, size isnt an issue, im building this box strictly for this comp so sound quality is absolutly no issue....

thanks for the help

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[MikeofTulsa Moderator]

well check the following site....it will tell u the best possible box size for a given power range.......

http://www.adireaudio.com/mobile_audio/drivers/brahma_power_handling.htm

 

[F150Matt 10+ year member]

Dont go by that crap. If your competing you for sure dont want a sealed box...how much power are you using? This will determine how big you can make the box and how big you can make the port. What type of vehicle are you using? All of these factor into tuning frequency and box size...

 

[audio hoe 10+ year member]

running off a jbl1200.1

going in a dodge durango, the sky's the limit box size wise...

any help will be apreciated

thanks

 

[F150Matt 10+ year member]

I'd start with about 6 cubes and 180-200inches of port. Try to find your resonant frequency and tune the box to peak at that. You should be able to be pretty succesful with it. Its all trial and error...make that port removable, and try increasing and decreasing port area, try changing box positioning in the vehicle...all of these things can make or break your SPL. It takes a lot of work to get it right. Good luck.

 

[BDIDDY 10+ year member]

how do you find the resonant frequency?

 

[bigbassman Premium Member]

if you have access to an spl meter.. you build, and keep adjusting the port till its loudest.. whatever frequency that is at, is your resonant..

if you don't have access to a meter.. you guess..

Loyd L.

 

[BDIDDY 10+ year member]

is there a good number to start at. and can the right number make that much of a difference?

 

[F150Matt 10+ year member]

Yes that number can make a significant difference. I suggest you get to know a few guys at a local shop, one that has a meter, and get them to let u use it for an hour or so. May wanna try a lil less than the port area I suggested earlier too, I forgot you only have a JBl 1200.1. You might want to start with 100 inches and go up from there. I think thats what I am gonna do with my XXX 15 when it comes in...David seems to think a one to one ratio would be good for port area...try it with your brahma.