Sub/box issue

[The Camry]

Ive got an sa-12 in a 2.2 cuft box ported to 32 hz. running it on 1000rms. now for most songs, Tight great sundown bass but other songs, It gets really boomy. like i can almost hear the bass im supposed to be getting covered with a layer of just boom. I dont mean bass you can feel, but bass you can hear. Its the subwoofer for sure as well because if i use the gain knob and lower it to nothing, it disappears.

What in the world can cause this? its really start to get on my nerves. Thinking about just building a 4th order and transferring the sub over. Is there any chance its the actual subwoofer or do you think it could be the box?

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[Jeffdachef 5,000+ posts]

Put those boomy sounding songs on audacity and analyze the spectrum and see what hz your sundown is boomy with. It could be your vehicles's peak frequency. Also whats your sq inches of port area per cubic feet ratio.

 

[The Camry]

I didnt design the box, jjust built it so i dont remember the dimensions. Port is 15 1/2 L x 2 1/4 W X 14 H

Does that give you enough info?

Pic was before adding last part on the left to make front facing port

 

[Jeffdachef 5,000+ posts]

I didnt design the box, jjust built it so i dont remember the dimensions. Port is 15 1/2 L x 2 1/4 W X 14 H

Does that give you enough info?

Pic was before adding last part on the left to make front facing port

Whats th height, width and depth of the box? This might totally be an enclosure design problem, in fact im pretty sure of it.

 

[negolien]

Whats th height, width and depth of the box? This might totally be an enclosure design problem, in fact im pretty sure of it.

....

 

[The Camry]

16x 16 1/2 x 26 3/4

Thats the full box. Port and all.

I could pull out the sub and find the actual internal measurements if its necessary.

im down to build a new box if someone wants to throw me a design. I dont mind paying for it. I cant seem to get ANY help on here for designing a box

 

[Jeffdachef 5,000+ posts]

16x 16 1/2 x 26 3/4
Thats the full box. Port and all.

I could pull out the sub and find the actual internal measurements if its necessary.

im down to build a new box if someone wants to throw me a design. I dont mind paying for it. I cant seem to get ANY help on here for designing a box

You are currently tuned to 40hz after sub, and port displacement not 32hz with 2.56 net cubic feet with a very small sq inch port area per cubic feet ratio of 11 ish. You can easily modify your box by adding 16.5 inches of port length to your box and you will get 34hz tuning at 2 cubic feet net. Port per cube ratio of this one is 15.67, you will see a big difference in low frequency output and less peakiness you are getting in the 45 to 55hz range.

If you dont know the proper port length to add on in the wood wall wise, you can just do a whole new box, just let me know your max dimensions.

 

[The Camry]

Hm that'd explain why i feel like im over excurting on some songs and the loudest song i have is X-rated by Excision which is a very 40hz area song.

 

[The Camry]

so just adding 16.5 port like this ??

Dem art skills

 

[Jeffdachef 5,000+ posts]

If you are going to do a 4th order, for sure go with dcarcustoms for a design. Sundowns get pretty crazy in 4ths.

 

[The Camry]

Alright thanks a ton

 

[The Camry]

so i finally said screw it and took the box apart. Is it still tuned to 40hz like you said?

 

[Jeffdachef 5,000+ posts]

You gave me a totally incorrect port length lol. Port length is not how long that piece of wood that you are using for the port wall is. Port length is measured straight down the port.

To give you an example of what i mean *OFFICIAL* Free Ported Box Plans (56k NO!!) - Dodge SRT Forum

Look at the designs on that site, the red line in each enclosure is the port length.

 

[The Camry]

ah i see. So im curious. If i play anything in the 32hz range loudly. I can hear that over excursion click click.

Any idea why this is?

Enclosure Suggestions: 1.75 ft^3 ported tuned to 30 Hz -- F3 of 26 Hz * Tune higher and use a smaller box for more SPL oriented setup (Use 1 - 1.5 cubes) * Enclosure can be as big as 2.25 ft^3 with lower power levels 1.00 ft^3 sealed -- F3 of 44 Hz * For SQ and space limited applications

Is it because im giving it 1000rms instead of the rated 600, that im getting over excursion?