Design box for New DD 2512c with FS: 44.41hz

[Eclipse25]

Hi I need some help designing a box for Digital Designs 2512c D2.

Fs:44.41hz

Qts: 0.866

Qes: 0.987

Qms: 7.061

Vas: 15.51 L

The sub will be wired to rockford fosgate 1200R @ 1ohm

Tuning 44hz or 40hz or 35hz or 32hz i dont know what is the best

[CleanSierra]

Are you sure the Qes is .987?

If so, that sub is strictly for a sealed enclosure. A 4th order bandpass is an alternative but that requires some experience.

[Eclipse25]

Yes, say dd audio.com

http://www.ddaudio.com/products/mobile-audio/woofers/2500-series

[IzZy2Loud4U]

I had a whole typed but IE sucks with this forum. long story short I has 2.5 cub each sub separate chambers 2 4" ports per chamber tuned at 35 HZ and did 144.6 db on term lab in the kick with the wide half of the back seat up. cut the ports down for 41 HZ and it was way better. subs up port back box was as far back as possible and as short as possible (under 12" tall) yellow top in back audiopipe 3000.1d never had the chance to get metered after changing the tune. Ill link you to my youtube when I switch to my other computer with chrome. vids are cheesy but you can see them flex and my box.

[Eclipse25]

I would like to see your photos or videos, would serve me much help. Thank you

[Guest]

from DD website

http://www.ddaudio.com/sites/default/files/media/products/dd_boxes/compact_box_plans/12_inch/12_compact_size.pdf

[Eclipse25]

Thanks for your help, and had seen the box designs ddaudio.com but the problem I see is that they are generic designs, and this sub with Fs: 44.41hz seems special. any other suggestions?

[CleanSierra]

Thanks for your help, and had seen the box designs ddaudio.com but the problem I see is that they are generic designs, and this sub with Fs: 44.41hz seems special. any other suggestions?

The Fs spec alone doesn't dictate how low a sub will play, or optimal enclosure. That spec combined with the Qes will tell you the Efficiency Bandwidth product [as determined by Richard Small, (the guy who in part created T/S specs)].

An EBP from 0-50 is a subwoofer suited for a sealed enclosure(or 4th order bandpass). A sub with an EBP of 50-100 can either go sealed or ported. 100 and above is typically only suited for a ported enclosure.

Efficiency Bandwidth product is calculated by dividing Fs by Qes.

[CleanSierra]

Your EBP is at 44.98(45). The sub you have is best suited for a sealed enclosure. IF you want to run a ported box with that sub, it's not ideal at all. IF you want to run it ported, I'd suggest a higher tune, close to 40Hz.

[Triticum Agricolam]

I was just about to respond when CleanSierra beat me to it.

I'm pretty much going to tell you the same thing as he did. Its EBP is low and is in what is usually considered sealed-only territory, though I have seen other subs in that EBP range in ported boxes.

If you are going to put it in a ported enclosure I would suggest 1.5 - 2.5 cubic feet net tuned to around 37 Hz or so. On the larger end of that size range will get you more low end output, but it will be more peaky, personally I shoot for 1.5 cubes, but that's me.