Stuffing? Or porting? Suggestions?

[datman]

I recently installed 2 10" subwoofers in my 2007 f150. since there is limited room I had to go with a box with 2 ft3 of airspace combined (1 ft3 per sub) at low volumes, it sounds really good, but at mid/high volumes, the quality of the lows really suffers-

so here's what's happening.

I wish I could explain whats happening better, but i'll try anyway. when listening to it at low volume the low notes sound as they should. as the volume increases, so does the frequency seem to increase (the same note seems higher than before)

so Here's what my research has brought me to-

As I see it I have 2 options, attempt to fill the box with polyfill, or to port it, port length calculator suggests 2"x4" port , but my box is only 5.5" tall... below it shows a much larger port is needed..

here's the recommended specs from the company on enclosure size

Port Frequency: Small = 47 Hz; Large = 45 Hz

Ported Enclosure: Small = 0.8 CuFt; Large = 1.2 CuFt

Sealed Enclosure: Small = 0.6 CuFt; Large = 1.2 CuFt

Port Diameter: Small = 3 "; Large = 4 "

Mounting Hole Diameter: 9316"

Port Length: Small = 8.5 "; Large = 11 "

Dimensions (H x L x W): : 4.02" x 10.55" x 10.55"

suggestions?

Click to read more...

 

[adulbrich 5,000+ posts]

Not enough box volume for ported. Try polyfill, but ultimately, your box is probably too small.

 

[C1500martin 10+ year member]

Porting will probably make it worse. Box is too small add polycill and keep it sealed but thats the best youll get. Maybe change out subs to something that like small enclosures such as dayton HO

 

[wew lad 5,000+ posts]

It'd help to know what subs you're using.

You can try stuffing some polyfill in there (it's cheap) and see what happens. Keep it less than a pound and a half of fill total and you should be good, start with half a pound, then a pound. It'll make a difference, but it may not make the difference you want. Try it out, see what happens.

edit; martin, why would adding polyfill to a small box make it worse? You very well may be correct, but from my research it should help, unless the box is ridiculously stuffed of course..

nevermind, misread

 

[Jeffdachef 5,000+ posts]

box is too small to port man. Either add polyfill or build a new box(best choice).

edit; martin, why would adding polyfill to a small box make it worse? You very well may be correct, but from my research it should help, unless the box is ridiculously stuffed of course..

he said porting will make it worse not polyfill.

 

[trumpet 5,000+ posts]

I'm guessing what you're attributing to poor deep bass is a mismatch between the mid and high frequencies in relation to the bass. Basically it is inadequate deep bass, but the response of the subs isn't what's changing.

 

[Jeffdachef 5,000+ posts]

yeah its not the tone changing, its just the upper bass is peaking harder than the low notes. Need a proper ported enclosure tuned to low 30s and NO a 2 inch aeroport is not enough port area for two 10s at all, thats a recipe for port noise disaster and cr@ppy sound/low output.

 

[datman]

Thanks guys, I'll try polyfill. I cant make a bigger box without taking out the rear seat in my truck, it is the biggest box with the most airspace I could find. Anything is worth a shot at this point, so hopefully some polyfill would help.

... im hoping this is the problem and not my soundstream processor.... (fingers crossed)

 

[wew lad 5,000+ posts]

I was in your situation once, lol. Ended up pulling the backseat and using the box as a back seat... building subs in the cab of a truck under the back seat with a box any larger than ~2 cubes or so is pretty much impossible, depending on the trucks design of course

 

[Savackz]

Do 2 8s then.

 

[datman]

last question, where do you get your polyfill? I've seen a lot of posts of people going to the craft store and getting polyester pillow batting... is this ok? or can someone help me out with a link of a good quality product?

 

[wew lad 5,000+ posts]

i used the cheap stuff from wallyworld, works fine. there's an "ideal" type, but the cheap stuff works just fine

 

[Jeffdachef 5,000+ posts]

walmart. Same stuff as expensive stuff.

 

[Boominburban]

I would almost bet a pair of E8v3's would sound better than what you have now by far ...

 

[gckless 5,000+ posts]

Are you sure you set everything well? Distortion can do what you described if you're getting to that point.