how will my new system compare to my last?

[maljr1980 10+ year member]

i had 4 12" L7's in a sealed box on 2600 watts, i had 2 alpine pdx m12's. i got rid of the L7's about 3 months ago. today i traded one of my amps for 2 10" alpine type x's in a slot ported box and some cash in my pocket. its a box built to specs, not sure the volume. im interested to see how loud these 2 10's can get on 1300 watts. i know it wont be as loud, i have half the power and alot less cone area, but i should make a little bit up with the ported box.

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[Serpent710 10+ year member]

the 12 l7s should be a lot louder even though they were sealed.

 

[maljr1980 10+ year member]

half the power and half the surface area should be 6 db's, and they are 10s, not square 12's so i say 8 dbs, add 3 back for the port, so i imagine i lose around 5 dbs, sound right?

 

[Heeltoeclutch 10+ year member]

half the power and half the surface area should be 6 db's, and they are 10s, not square 12's so i say 8 dbs, add 3 back for the port, so i imagine i lose around 5 dbs, sound right?

...is there a magic calculator I can use to get numbers like these? //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[wickedwitt 10+ year member]

the 12 l7s should be a lot louder even though they were sealed.

This, while you gain a ton of output by moving to ported, you lost more than half of your cone area and half of your power. Lost a lot of sound, probably gained some low end response.

 

[WheresTheButta 10+ year member]

the 12 l7s should be a lot louder even though they were sealed.

truth. the L7s have a LOT more cone area; in fact they have nearly 4x the cone area of the type X woofers. The 4 L7 12s have approx 576 sq inches of cone area while the pair of type X woofers only has 157... If you hold everything else equal, a ported box has the potential to gain 3db at the tuning frequency over a sealed box, but you're not holding everything else equal. You lost so much cone area and cut your power in half...

 

[wickedwitt 10+ year member]

...is there a magic calculator I can use to get numbers like these? //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

I'd assume 4-5 db too, but not using his theory. There is no magic calculator and the exact same changes in 2 identical vehicles will net a completely different gain/loss on the meter.

I'm going to be tripling cone area and quadrupling power, and we are HOPING for a 6db gain. That's being VERY optimistic.

 

---------- Post added at 10:10 PM ---------- Previous post was at 10:10 PM ----------

 

...is there a magic calculator I can use to get numbers like these? //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

I'd assume 4-5 db too, but not using his theory. There is no magic calculator and the exact same changes in 2 identical vehicles will net a completely different gain/loss on the meter.

I'm going to be tripling cone area and quadrupling power, and we are HOPING for a 6db gain. That's being VERY optimistic.

 

[wickedwitt 10+ year member]

Double quote inside the same post.

What is this I don't even...

 

[maljr1980 10+ year member]

the magic calculator is in theory 2x power is + 3db, 2x S.A. is + 3db, and ported vs sealed is + 3db. that is all theory. also how are you calculating cone area, you have to subtract for the size of the surround, and the distance in from the outside of the basket that the surround starts. S.A. of a 12 " woofer isnt pi(6)^2, its more like pi(4.75)^2, but thats besides the point. id say i have a 3rd of the surface area. thats how i came up with my numbers as to what i should expect. i havent had any music at all since i sold my 12's since i pulled all my amps out. this is basically a winter system. when i get some cash saved i plan on 4 15" dc lvl4/5's and a dc 5k. i know this will just tease me and **** me off, but at least i'll have a little thump untill i get around to the big install

 

[Oh6AcCoRd 10+ year member]

It'll be more quiet, but i bet it will sound better, I had 2 l7s on 1500. I hated the sound of them. Maybe its just me but I'm far from a fan of kickers subwoofers.

 

[wickedwitt 10+ year member]

the magic calculator is in theory 2x power is + 3db, 2x S.A. is + 3db, and ported vs sealed is + 3db. that is all theory. also how are you calculating cone area, you have to subtract for the size of the surround, and the distance in from the outside of the basket that the surround starts. S.A. of a 12 " woofer isnt pi(6)^2, its more like pi(4.75)^2, but thats besides the point. id say i have a 3rd of the surface area. thats how i came up with my numbers as to what i should expect. i havent had any music at all since i sold my 12's since i pulled all my amps out. this is basically a winter system. when i get some cash saved i plan on 4 15" dc lvl4/5's and a dc 5k. i know this will just tease me and **** me off, but at least i'll have a little thump untill i get around to the big install

If you're going to subtract for surround, you need to measure it. You can't just guestimate. His calculations were done off the general agreement of a speakers cone area (2pie x Radius x # of cones) for rounds and (l x w x # of cones) for squares. If you want to get technical, you'd have to take efficiency of the boxes, woofers, excursion etc etc. Just going off of cone area and power, however, you lost a ton of output potential.

 

[maljr1980 10+ year member]

oh and im half tempted to scrap the box and put them in a sealed box so they really shine, but im afraid they will be too underpowered in a sealed box, plus i would lose way to much sound. i could do a wall behind the front seats and lose 75% of my cabin area and they might slam

 

[wickedwitt 10+ year member]

It'll be more quiet, but i bet it will sound better, I had 2 l7s on 1500. I hated the sound of them. Maybe its just me but I'm far from a fan of kickers subwoofers.

GTFO, I'm kidding (or am I?)

I agree the L7s had a bit of a sound to them. It's much less noticeable with the X's, however.

 

[maljr1980 10+ year member]

i never asked which would be louder, i just wondered how much output i would lose. they kind of fell in my lap on a trade to get me a little music untill i do a bigger build than what i had before. i thought it was a decent trade. and it may be an sq setup in a second vehicle down the road, most likely a little fuel economy car

 

[wickedwitt 10+ year member]

oh and im half tempted to scrap the box and put them in a sealed box so they really shine, but im afraid they will be too underpowered in a sealed box, plus i would lose way to much sound. i could do a wall behind the front seats and lose 75% of my cabin area and they might slam

If I were you (which I am not) I wouldn't lose that much cabin area just for 2 10s (especially SQ leaning ones) that are meant to be temporary.Just own up to the fact that it won't be as loud as it was, and bide time until you can do that 4 15 build you are wanting.