Cone Area Relation Chart

Mods: I think you should sticky this, or suggest another title for the thread and sticky the new thread. This will reduce a lot of threads that ask "How many X sized speakers does it take to equal the cone area of nX sized speakers?" and also hopefully be a quick reference sheet for even the experienced to look at.

THESE NUMBERS ARE NOT EXACT! I rounded for almost all of the numbers, and for the charts that compare X speakers to nX speakers, I only picked those that were closely related in cone area. Since my calculator does not have a Pi function, I multiplied the radius squared by 3.14, which as most of you know is close enough. This chart is only meant to give you an idea of how similar the cone area of X speakers is to nX speakers.

As you can tell, I only went for common sized speakers. I'm not going to include speakers like the ear-shaped Yamaha woofer, or some one-off sub like the custom MTX Thunder 1,000,000. The sizes I chose are those of known production speakers (off the top of my head). Please let me know of any that I left out, and I will update each category to include them.


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One Speaker

Diameter of speaker | Cone area of speaker in square inches

34" ---> 908
32" ---> 804
22" ---> 380
21" ---> 346
18" ---> 254
15" ---> 192
13.5" ---> 143
12" ---> 113
11" ---> 95
10" ---> 79
8" ---> 50
6x9 ---> 42
6x8 ---> 38
6.5" ---> 33
4x10 ---> 31
5x7 ---> 28
5.25" ---> 22
4" ---> 13
3.5" ---> 10
2" ---> 3


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Two Speakers

X Speaker | Equivalent of 2X Speakers

3.5" ---> 5.25"
4" ---> 5x7
5.25" ---> 6x9
5x7 ---> 8"
6x8/6x9 ---> 10"
8" ---> 11"
10" ---> 13.5"
11" ---> 15"
12" ---> 18"
15" ---> 22"
22" ---> 32"


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Three Speakers

X Speaker | Equivalent of 3X Speakers

2" ---> 3.5"
3.5" ---> 5x7/4x10
4" ---> 6x8/6x9
5x7 ---> 10"
4x10/6.5" ---> 11"
6x8 ---> 12"
8" ---> 13.5"
10" ---> 18"
12" ---> 21"
18" ---> 32"


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Four Speakers

X Speaker | Equivalent of 4X Speakers

2" ---> 4"
3.5" ---> 5x7/4x10
4" ---> 6x8/6x9
8" ---> 15"
10" ---> 21"
11" ---> 22"
15" ---> 32"

This chart displays the relationship between odd shaped subwoofers and circle subwoofers. You may know the triangle and pentagon subwoofers from Bazooka and Xtant, respectively, and the 24" square subwoofer as the new MTX Jackhammer.


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Pentagon

One Subwoofer

Diameter of Cone | Cone Area in square inches

10" ---> 74


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Pentagon

Two Subwoofers

X Subwoofer | Circle Subwoofer Equivalent of 2X Subwoofers

10" ---> 13.5"


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Pentagon

Three Subwoofers

X Subwoofer | Circle Subwoofer Equivalent of 3X Subwoofers

10" ---> 15"/18" (between the two)


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Pentagon

Four Subwoofers

X Subwoofer | Circle Subwoofer Equivalent of 4X Subwoofers

10" ---> 18"/21" (between the two)


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Triangle

One Subwoofer

Diameter of Cone | Cone Area in square inches

10" ---> 48
12" ---> 86


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Triangle

Two Subwoofers

X Subwoofer | Circle Subwoofer Equivalent of 2X Subwoofers

10" ---> 11"
12" ---> 15"


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Triangle

Three Subwoofers

X Subwoofer | Circle Subwoofer Equivalent of 3X Subwoofers

10" ---> 13.5"
12" ---> 18"


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Triangle

Four Subwoofers

X Subwoofer | Circle Subwoofer Equivalent of 4X Subwoofers

10" ---> 15"
12" ---> 21"


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Square

One Subwoofer

Diameter of Cone | Cone Area in square inches

8" ---> 64
10" ---> 100
12" ---> 144
15" ---> 225
18" ---> 324
24" ---> 576


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Square

Two Subwoofers

X Subwoofer | Circle Subwoofer Equivalent of 2X Subwoofers

8" ---> 12"/13.5"
10" ---> 15"
12" ---> 18"
15" ---> 24"


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Square

Three Subwoofers

X Subwoofer | Circle Subwoofer Equivalent of 3X Subwoofers

8" ---> 15"
10" ---> 18"/21"


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Square

Four Subwoofers

X Subwoofer | Circle Subwoofer Equivalent of 4X Subwoofers

8" ---> 18"
10" ---> 22"
12" ---> 34"


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2 15's is considerably larger than 1 21".

hmmm...

Quote:

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Originally Posted by CHEMMINS

2 15's is considerably larger than 1 21".

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That was one of the ones I was iffy about. It's about 40 cubic inches difference, which is about 10% marginal error. I don't think that it would be audible?

Thanks for the input! Anyone else feel free to help improve this!

Quote:

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Originally Posted by CHEMMINS

2 15's is considerably larger than 1 21".

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And four 10's is pretty much exactly the same sd as one 18, not one 21.

Quote:

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Originally Posted by RAM_Designs

And four 10's is pretty much exactly the same sd as one 18, not one 21.

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4 10's would be 314......no?

Quote:

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Originally Posted by CHEMMINS

4 10's would be 314......no?

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I'm just going off of Fi's specs. 1240cm^2 for the four 10's and 1210cm^2 for the 18.


OP: If you're going to do the whole pi(r^2) thing, take 3" off of each normal-sized woofer's diameter since you have the mounting ring and surround on each side to consider when looking for a somewhat accurate idea of the cone size.

Or just look around for normal sd measurements on different size woofers.

so 2 8s same as 1 12? gona do 4 8s instead of my 4 12s.looks like im gona lack the cone area i guess

Quote:

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Originally Posted by RAM_Designs

And four 10's is pretty much exactly the same sd as one 18, not one 21.

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79*4=316
18"=254
21"=346

Quote:

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Originally Posted by RAM_Designs

I'm just going off of Fi's specs. 1240cm^2 for the four 10's and 1210cm^2 for the 18.


OP: Sd isn't just a flat thing that you can measure by looking at the radius of a woofer, cone angle comes into play as well. And if you're going to do the whole pi(r^2) thing, take 3" off of each normal-sized woofer's diameter since you have the mounting ring an surround on each side to consider when looking for a somewhat accurate idea of the cone size.

Or just look around for normal sd measurements on different size woofers.

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Alright buddy, you're making things waaaay too technical :) Like I said in the title, the measurements are not exact.

You are going by the cone area of a specific subwoofer, whose basket is measured to be 8/10/12/15/18". My chart compares ACTUAL cone area, so it rules out angle, surround width, etc.

If I measured your way, I would be required to put every single sub ever made in existence, separately, on this chart. I'm sorry bruh, but I don't have the time for that lol

Quote:

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Originally Posted by 1mtx1

so 2 8s same as 1 12? gona do 4 8s instead of my 4 12s.looks like im gona lack the cone area i guess

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Nope :/ 2 8s is similar to 11". The marginal error of 2 8s to 1 12 is about 13%. Honestly though, that's not gunna be an audible difference, but still.

Quote:

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Originally Posted by Troll Face

Nope :/ 2 8s is similar to 11". The marginal error of 2 8s to 1 12 is about 13%. Honestly though, that's not gunna be an audible difference, but still.

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so i should b ok then. im gona do 4 8s tune to 32 instead of 4 12s sealed. the power will b the same i just will b doing four lower rms subs that will see close to there rated power where my 12s where seeing about half there rated power with my curent amp. thanks good write up might i add my luv

Quote:

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Originally Posted by 1mtx1

so i should b ok then. im gona do 4 8s tune to 32 instead of 4 12s sealed. the power will b the same i just will b doing four lower rms subs that will see close to there rated power where my 12s where seeing about half there rated power with my curent amp. thanks good write up might i add my luv

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Yeah, good idea. It's fun to showoff to all the caraudio noobs you know, then tell them you're running 8's :)

Thanks! It took hours upon hours, so I'm glad at least someone appreciates it...

Updated the first and second posts to include the Jackhammer 22" (first post), and the square, pentagon, and triangle subwoofers. Again, feel free to critique!

Tomorrow, or whenever I find time next, I will go through and display the marginal error for every equivalence comparison. Other than that, I think that pretty much covers it!