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BDIDDY
06-29-2003, 08:20 PM
I was wanting to build another box because the 5.5 cuft. tuned to 50 hz is not cutting it sq wise. Just wondering you alls recommendations. I was thinking 4 or 3.5 but 3.5 would be a little more to figure out tuned to about 33 hz. I want your eyes to water and this thing to go extremely low. I dont know about the port size as I mean the area but any recommendations are welcomed.



Thanks.

BDIDDY
06-29-2003, 10:12 PM
Well I did it myself after looking at some posts on here and was wondering if this was right. It will be 4 and after looking at this other post the guy said to add the port and sub displacement to the net volume so I got 4.8. I think that is a little big but then I tuned it to 33 hz with the port being 13 high x 3 wide x 25.35 deep. I was wondering if the port face was to big to small or what? Look for how I want the sub to hit up top.


Thanks.

Trixter
06-30-2003, 12:46 PM
If you went 4cu' at 33Hz, you will get a huge spike of 7.8db at 35Hz.

If you want good sq and a strong low end, I would make a box 3.5cu' and port it to 24Hz. This would give you a pretty flat response with a slight peak of 2.5db at 26Hz. You will have a strong low end (between 22 and 38Hz) The brahma can do the low notes, that should sound pretty cool.
Oh yah, a port 3"w, 6"h, and 20.5"l should get you there.

BDIDDY
06-30-2003, 02:22 PM
Is there any way that you can chage that port to 13 high x whatever else? And what does the spike have to do with anything?

Trixter
07-01-2003, 09:52 AM
You could go with 13"h x 2"w x 28.5"l

For good sq you are looking to get a "flat" response. In short, this means that all freq's. will be reproduced at the same volume. For an ideal spl box, you would be looking for a large peak at the freq. you are trying to achieve. But by doing this the box will only correctly reproduce the desired freq. Personally, what I like to do, is make a box that has a slight peak at the lower end, because I like low end bass, and then keep it flat from there on up to maintain my sq.

bumpin_blazer
07-01-2003, 10:01 AM
Originally posted by Trixter
You could go with 13"h x 2"w x 28.5"l

For good sq you are looking to get a "flat" response. In short, this means that all freq's. will be reproduced at the same volume. For an ideal spl box, you would be looking for a large peak at the freq. you are trying to achieve. But by doing this the box will only correctly reproduce the desired freq. Personally, what I like to do, is make a box that has a slight peak at the lower end, because I like low end bass, and then keep it flat from there on up to maintain my sq.

my question is why make the box so big?? why not go for a lil bit smaller box and tune it low like trixter said?? i agree that tuning it to 33hz is good but i'd go lower in the upper 20hz range.

adam

Trixter
07-01-2003, 10:24 AM
Yah, the only reason I suggested to tune it so low is so you can get a samll peak in the upper 20Hz range. I normally wouldn't do this, but I know that the Brahma can do it nicely. You could also go with a smaller box and still get the freq. you are looking for by changing the port size. In fact, WinIsd reccomends a 2cu' box ported to 25Hz to get a flat response. I just increased the box size a little to get a stronger low end.

BDIDDY
07-01-2003, 12:03 PM
So go with the 3.5 ported right? Yeah after I thought about it, it was too big. But thanks for the help and enlightening me on peaks and stuff like that. I understand that much more.