Getting Low, adding cone weight?

[jolly_26 10+ year member]

Got a box sitting around tuned to 30Hz and found that when my subs were in it they didn't kill lows as well as I hoped, what does it take to get subs to hit those lows? This is not a box problem. What would happen if I added weight to the cone to lower the Fs? Would it by any chance decrease mechanical power handling etc? My subs are cheap, and have a fs of about 37Hz which seems reasonably high for a 12.

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[hispls 5,000+ posts]

Adding mass to lower Fs will kill efficiency. Depending on the stiffness of suspension you'd need to add way too much mass to make that an effective strategy.

What subs? What vehicle? what are the box specs?

 

[jolly_26 10+ year member]

fair enough just a thought. Pioneer champions, 3 cube box at 30Hz, 48sq. inches of port. Going to give the subs a real thrashing then either have a go at a re cone myself or import some decent subs. In that box they were gained to 575 rms each, and took it well, I was really surprised by that. And they're in the trunk of a Mazda Sentia, actually in a sealed box now to free up boot space but was going to give them a last run in the ported box to see what they could do.

 

[murph 10+ year member]

I would say different subs will benefit you.

 

[hispls 5,000+ posts]

Going to be limited by the ability of those woofers Im afraid. I had a very stiff woofer I built and did some testing with adding mass....took about 1KG to drop Fs by 10hz. I've heard of guys doing it with like 5 1/4 woofers in strange application, but really the only thing it does is prove the point that it works, it certainly won't work well.

 

[jolly_26 10+ year member]

I would say different subs will benefit you.

Haha yes definitely, was basically wanting to have some fun with them while they last.

Going to be limited by the ability of those woofers Im afraid. I had a very stiff woofer I built and did some testing with adding mass....took about 1KG to drop Fs by 10hz. I've heard of guys doing it with like 5 1/4 woofers in strange application, but really the only thing it does is prove the point that it works, it certainly won't work well.

Wow putting a Kg on the cone would have surely caused some pretty large stress? What was the sub?

 

[hispls 5,000+ posts]

Haha yes definitely, was basically wanting to have some fun with them while they last.


Wow putting a Kg on the cone would have surely caused some pretty large stress? What was the sub?

18" Shocker Neo sig. What killed me was the aluminum coil and super stiff spider pack I used. Copper coil and slightly softer suspension makes for much better specs on that motor.

An extra KG would have really thrown efficiency out the window. My thought was I could layer some CF over the cone or just lay up a really thick dustcap if say 100 or 200g would have made a difference.

 

[njknittle 10+ year member]

3 Cubes seem rather small for 30hz. Idk if its just me but when guys are running a box at 30hx and below the box is bigger than at least 4 cubes

 

[murph 10+ year member]

3 Cubes seem rather small for 30hz. Idk if its just me but when guys are running a box at 30hx and below the box is bigger than at least 4 cubes

If it is a slot port there is so little left for the subs.

 

[njknittle 10+ year member]

If it is a slot port there is so little left for the subs.

Could be part of the problem?//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

 

[murph 10+ year member]

Could be part of the problem?//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

//content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

 

[RAM_Designs 5,000+ posts]

3 Cubes seem rather small for 30hz. Idk if its just me but when guys are running a box at 30hx and below the box is bigger than at least 4 cubes

x2, volume could be a problem also, although I agree with hispls that the woofers themselves are probably limiting you more than anything...they're just not made to pound the lows like you expected. Find some woofers with a lower Fs and more excursion, and you'll likely notice a big difference.

I'd still recommend going with a bigger box if you're looking for prominent lows though. I ran a pair of 10's in a 4ft^3 @ 28hz box and they sounded great in the 25-50hz area, and the slowly rolled off on the top end, which I prefer anyways. Granted, they had the right specs and capabilities to perform well on the lower side of things.

 

[njknittle 10+ year member]

x2, volume could be a problem also, although I agree with hispls that the woofers themselves are probably limiting you more than anything...they're just not made to pound the lows like you expected. Find some woofers with a lower Fs and more excursion, and you'll likely notice a big difference.
I'd still recommend going with a bigger box if you're looking for prominent lows though. I ran a pair of 10's in a 4ft^3 @ 28hz box and they sounded great in the 25-50hz area, and the slowly rolled off on the top end, which I prefer anyways. Granted, they had the right specs and capabilities to perform well on the lower side of things.

//content.invisioncic.com/y282845/emoticons/bowdown.gif.b85b23b82970bd22fb6b549c3392f016.gif The master of Subwoofer Boxes!

 

[jolly_26 10+ year member]

yeah the box is 3 cubes after all displacement, and I really don't have the room to run any bigger, will look at different design options though I guess. Trying to sell the Mazda atm and get either a Stagea or an r31 Wagon, so would have more room all round.