which is louder 13w7 or 4 8w7

[deagle44cmag 10+ year member]

A kid from work offered me 1500 dollars for my 13w7 and 500/1. I am debating to sell or not because i want to keep the loudness and clarity of the system. I did some math to see how much air each moves and the 13w7 moves more then 4 8w7s can anyone show me if i made a mistake in the math. 13w7) surface area pi*r^2 6.75in^2=45.6 45.6*pi=143.3 xmax=1.25in 143.3in*1.25in= 179.1 cubic inches 8w7)16*pi=50.3 50.3*4 speakers= 201.1in xmax=.75 201.1*.75=150.8 13w7=179.1>150.8=4*8w7 they both mill come to 1000 watts 1000w-13w7 250w-8w7

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[thadman 10+ year member]

definetley do that!

You could get 2 15" Stereo Integrity Magnums and an Incriminator Audio 20.1/Orion 2500D/Anything from US AMPS for that much $$$

but to answer your question

The 8s have 200in^2 of surface area and the 13.5 has 143in^2.

82.3 @ 1 x 1 (1 driver)

88.3 @ 2 x 2 (double the displacement + equal power to each driver)

94.3 @ 4 x 4 (4 drivers total, another doubling of displacement + equal power to each driver)

97.3 @ 8 x 4

100.3 @ 16 x 4

103.3 @ 32 x 4

106.3 @ 64 x 4

109.3 @ 128 x 4

112.3 @ 256 x 4

115.3 @ 512 x 4 (4 8s on the 500/1)

118.3 @ 1024 x 4

86.3 @ 1 x 1 (1 driver total)

89.3 @ 2 x 1

92.3 @ 4 x 1

95.3 @ 8 x 1

98.3 @ 16 x 1

101.3 @ 32 x 1

104.3 @ 64 x 1

107.3 @ 128 x 1

110.3 @ 256 x 1

113.3 @ 512 x 1 (1 13.5 W7 off of the 500/1)

116.3 @ 1024 x 1

 

[Chevyaudio 5,000+ posts]

Yeah, Im pretty sure you can find a new 13w7 and 500/1 for less than that. so I say take advantage of that price that guy is offering you

 

[deagle44cmag 10+ year member]

I am thinking about taking the offer but then i have to build a new box and buy all the stuff off ebay again and i really dont have time for that i just want somthing louder then the 13w7 but from jl 2 12w7s?

 

[thadman 10+ year member]

If I were you, I'd take that offer and buy 1 15" Si Magnum D2 and an Arc Audio 2500XXK

#1 this setup would be louder

#2 It would sound just as good, if not better (the magnum is considered the best SQL sub on the market, yes greater than the W7)

#3 a 13.5 W7 needs about 1200-1500 to really get going, you're not giving it near its RMS with that setup

#4 You'd have an additional $500 to spend on whatever you'd like

 

[thadman 10+ year member]

There is a bnib 2500xxk on the forums $480 + s/h

http://www.caraudio.com/forum/showthread.php?t=148087&highlight=2500xxk

Here is a bnib 12" Mag

http://www.caraudio.com/forum/showthread.php?t=147561&highlight=si

another one

http://www.caraudio.com/forum/showthread.php?t=148022&highlight=si

You could probably get both for $700 shipped (wish SI still let you buy direct)

 

[Savstyle 10+ year member]

A kid from work offered me 1500 dollars for my 13w7 and 500/1. I am debating to sell or not because i want to keep the loudness and clarity of the system. I did some math to see how much air each moves and the 13w7 moves more then 4 8w7s can anyone show me if i made a mistake in the math. 13w7) surface area pi*r^2 6.75in^2=45.6 45.6*pi=143.3 xmax=1.25in 143.3in*1.25in= 179.1 cubic inches 8w7)16*pi=50.3 50.3*4 speakers= 201.1in xmax=.75 201.1*.75=150.8 13w7=179.1>150.8=4*8w7 they both mill come to 1000 watts 1000w-13w7 250w-8w7

good god what are u thinking about, go without a system for 2-6 weeks to make about 500 bux come on man thas not hard at all. And take thadmans advice 15 mag and that arc amp would be a awesome setup

 

[SATX210]

he probably has to clear it with mommy first

 

[deagle44cmag 10+ year member]

//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif satx why dont u shut up cuz ill throw the tantrum on the dub7 in my golf gti with the 2 sets of vr650-csi on a 4 channel 200 watt alpine amp with the clarion dxz655mp headuint n blow ur system up so stfu n have a nice day

 

[helotaxi 5,000+ posts]

definetley do that!
The 8s have 200in^2 of surface area and the 13.5 has 143in^2.

Don't know where you got your numbers, but they are off quite a bit. Sd of the 8W7 is 38in^2 each. Multiply by 4 to get the total: 152 in^2. The 13W7 has 107 in^ to work with. For straight piston area the 8s have the advantage. But that is only part of the equation. Total swept volume is the deciding factor in potential to get loud with a sealed system. The 1.25" Xmax for the 13W7 gives it a huge advantage over the 8s when you figure that in. 267.5in^3 vs 228in^3.

82.3 @ 1 x 1 (1 driver)88.3 @ 2 x 2 (double the displacement + equal power to each driver)

94.3 @ 4 x 4 (4 drivers total, another doubling of displacement + equal power to each driver)

97.3 @ 8 x 4

100.3 @ 16 x 4

103.3 @ 32 x 4

106.3 @ 64 x 4

109.3 @ 128 x 4

112.3 @ 256 x 4

115.3 @ 512 x 4 (4 8s on the 500/1)

118.3 @ 1024 x 4

86.3 @ 1 x 1 (1 driver total)

89.3 @ 2 x 1

92.3 @ 4 x 1

95.3 @ 8 x 1

98.3 @ 16 x 1

101.3 @ 32 x 1

104.3 @ 64 x 1

107.3 @ 128 x 1

110.3 @ 256 x 1

113.3 @ 512 x 1 (1 13.5 W7 off of the 500/1)

116.3 @ 1024 x 1

This is theory without actually figuring reality into the equation. It doesn't work even close to this in real life. If it did, you could just run 1kW to as many drivers as you could possibly fit into a car and break the SPL record. Sensitivity ratings are pretty much useless when figuring out how loud a sub can potentially get. The best approximation you would really be able to get is to run an excursion plot of each setup and figure it out from there.

 

[XtrmAudioCncpts 10+ year member]

8's FTW

 

[ssj2xxgotenxx 10+ year member]

Come on think about it.... make the profit and sell it. Then buy yourself some 8"s and give me the leftover money =D

 

[trow100 10+ year member]

You'd pretty much be retarded not to take this deal.

You could sell all your stuff and buy it back again online (all brand new) for less money. Even buy a 1000/1 probably.

Why do you HAVE to have JL audio? There are just as good products for half the cost.

Go with something different and you could easily have a better setup for at most $1000. Leaving you with $500 to go do whatever you want with as stated before.

 

[trow100 10+ year member]

The best approximation you would really be able to get is to run an excursion plot of each setup and figure it out from there.

Not debating what you said in your whole post about sensitivity ratings because you are right but wouldnt a xmax test only work for sealed enclosures?

 

[80INCHES 5,000+ posts]

1500bucks......omg....2 mag 15's and one ia20.1 or orion 2500d sounds reall nice

or u can get

8 rl-i8's...and have 2orion2500d's

80