CALCULATE SUBWOOFER BOX PORT AREA & CONE AREA W/ COMPARISON INFO

[@bassbuildscarlmeadors6650]

I have a sub cone chart that says two 15's are 353.25 inches of cone area. You calculated one 15

[@educated_guess]

i watched the video a few times and was confused by the 1 sub vs 2 sub math, but thank you for you comment. it cleared that up

[@christophervtec762]

Thanks for another great explanation of port & cone area Jacob now I understand a little better when it's broken down on paper it's much easier to understand specially when you have add 🤣

[@allizom4328]

I have just a wee bone to pick here. And while I know I'm really late in the reply, I feel it's worthy in case someone else comes across this like I did. What you did here is just calculate the surface area of a circle, not a cone. A speaker cone is a different beast altogether though. You have to calculate the diameter, radius, height, slant height, and the lateral surface area of the cone. However, in terms of a speaker cone, many, if not most have a partial sphere (dust cap) in the center which must be accounted for. There's generally some additional surface area added depending on how large the dust cap is. If it's the same size as the voice coil it's covering, then no additional surface area is added. However, if it's much larger like most are these days, then additional surface area is added to the cone. It can be calculated by measuring the length of the dust cap with a string as it is curved. Then use the formula for calculating the circumference of a circle using an arc: Arc length of AB / 2πr = mAB / 360° From there you need to multiply that single circle by 360 to get a sphere then use the formula for the surface area of a sphere: 4πr² Now we can calculate the surface area of the sphere segment using: A = 2πRh Now you have the surface area of the dust cap, measure the height between the bottom of the basket rim and the spider to get the cone height. Since we already know the diameter and thereby the radius, we can finish the calculations. You have to subtract the amount of surface area that is under the dust cap by calculating another simple cone calculation. Here are the relevant formulae: Volume of a cone: V = (1/3)πr²h Slant height of a cone: s = √(r² + h²) Lateral surface area of a cone: L = πrs = πr√(r² + h²) Base surface area of a cone (a circle): B = πr² Total surface area of a cone: A = L + B = πrs + πr² = πr(s + r) = πr(r + √(r² + h²)) 3:09

[@jedpetersen3806]

It's really too bad that after a month of your post I'm the only thumbs up. I'm afraid most people who would watch this video just take it face value and others like you and myself are watching it just too see if they know what they're doing. At least that's one of my reasons that and it's just cool to see other builds😎

[@blackfrost273industries4]

on the surface area of the dust cap at the end. do you not divide by two since the bottom half of the dust cap is not utilized in the cone? also trying to figure why the first formula ends with dividing by 360 and then you state to multiply by 360 to get the sphere. not trying to say you are wrong or challenge you. wanting to clarify more.

[@richfish3262]

I work in the trades that is an excellent use that did not think of for my box for rounded ports tape is made for flowing air what a great ingenious adoption into the process my box too is going to have it

[@04tb2]

Love these knowledge videos and how you break it down thanks Jacob 👍👍

[@noahkb80]

A dead give away of a highly intelligent, highly functioning brain - their body can't keep up with their brain. Speaking, movement, etc. Even decision making can falter. Seriously. I think it's cool as shit too, to learn from someone who's in their element

[@mosessalazar7818]

Thank you Jacob keep up the good work with the videos he always have great content. Thank you for your time

[@DCBDesigns]

Dont these calculations change with different power levels and Net spaces?

[@JacobViral2]

Correct

[@jacoblittle3209]

I have a couple of questions. In cone area are you supposed to include the surround in your measurement? Second, whats the rule of thumb when it comes to aero ports and their port area to cone area ratio?

[@JacobViral2]

Subwoofer size was used for cone area not the cone size itself. For concept some subwoofers cones are bigger then others while others are SPL, etc soon can vary slightly. You can measure port area of circular ports the same as square almost just circular is defined easier with being cylindrical just different formula. Idk the ratio for aerorport sorry.

[@jacoblittle3209]

@@JacobViral2 thanks for the info. I've just started making boxes with aero ports rather than slot port so I am trying to learn as much as I can when it comes to tuning and avoiding port noise

[@johnnycorn7225]

@@jacoblittle3209 the general rule of thumb is that you can get by with about 60% of the port area when using round as opposed to slots this is because the round shape evenly balances the air pressure resulting in even acceleration whereas the air accelerates in the corners and right angles of a slot which results in the chuffing sound. Also power compression is important if you're running more than 1,000 watts per cubic foot you should up your Port area a little bit to allow the extra air pressure to escape otherwise the smaller Port will choke the motion of the air that the power is accelerating. Aeros FTW

[@jacoblittle3209]

@@johnnycorn7225 damn man, that's the most information someone has given me on a KZbin comment. Thanx alot

[@johnnycorn7225]

No problem man I've had to hunt down that same information and the internet is nowhere near as helpful as you would think! I forgot if you want to really enhance your response around tuning frequency use the higher end of Port area like a full 20 square inches per cubic foot for slots or 12 if you're using aeros. If you are interested in hitting the higher frequencies of Base and are after a smoother more even response use a little less Port area for more bandwidth but you will get less peak at tuning. Are you after Max SPL or a nice even smooth response for music with a ported enclosure? Glad to help I know how it feels to be lost with it aero ports are so worth doing right

[@hbeezey]

bunch of gibberish, how tf would you tune a box then

[@lowhertzhighspl]

Great tip !! 👌🏻👍 (start with big port then shrink to liking) THX.

[@Joe-ok1ri]

Any help on a Richard Long (w ) style tunnel bass cabinet I know the design but don't know any measurements. it's for a 12 inch JBL or cerwin Vega box is 2 feet by 3 feet long?.

[@rubenflores2870]

Hey Jacob I've been learning a lot from you I have a ? My box that I built is Lx26Wx13D12 1/2 but I end up putting a 4"aero port. And I'm trying to figure out, what would be my length ? And I almost forgot my subwoofer is facing up it's a CT sound 10" strato . And my aeroport is coming out on the side of my box long ways . On the other side of my speaker so the opening end is underneath my magnet trying to figure out how far away from the would it needs to be. And Thank you for these videos They are really helpful 🙏💯

[@JacobViral2]

That depends on your tuning goal, probably around 18-20” length out but plug into a 12volt box calculator

[@rubenflores2870]

🙏💯 Thank you bro really appreciate your help 😎

[@Bassquatch_101]

Should have shown better how it looked on the calculator. I thought I was messing up cause it said 0.35 on it . So my box is 35% efficient

[@joseceraia]

What with QAS- VAS - Fs

[@alexgarza867]

Does anyone know to how to determine a box tuning without a program?

[@JacobViral2]

I made a video on this recently on my channel

[@mjl6425]

For the 215’s don’t you have to multiply the 176 by 2? Since there are two woofers and not just one like your 10inch?

[@JacobViral2]

Correct

[@mjl6425]

@@JacobViral2 Thanks. Quick question though I have 2 12s going into 4th order bandpass box. I Calculated 226 in.² for woofer displacement and 36 in.² for port area. This equates to 16% “Efficiency”. That is far off from your 72%. Is this bad?

[@JacobViral2]

@@mjl6425 I would go little bigger personally and mines so big because it’s a very big ratio. You’ll be fine

[@mjl6425]

@@JacobViral2 That’s what the box calculator gave me for 50hz tune and 30-85hz response. It should be good right?

[@bryanhicks4960]

So 176.625 is the amount of port needed for the 2 15s?

[@JacobViral2]

Depends on the box application and tuning goals

[@mpbraj]

You use your left hand or the right hand, I am completely zonked by the way you writing. Anyways thanks for the videos, however the port area you have taken only Length(height) and Breath, what about the depth of the port ? How it would be if its a round port, ?

[@JacobViral2]

I write weird lol. Port area doesn’t matter for depth long as it is parallel. Circle port is same concept but with circumference

[@Gravytrain815]

Does the length of the port come into play at all?

[@JacobViral2]

Yes, especially ported enclosures and 6th order rear tuning ports.

[@joeydelmarsjr.646]

i just did my port efficiency and its @ 0.20%

[@doublemanson]

🔴 so what percentage should we be aiming for? What if you have a square subwoofer, how do you account for the extra surface area.

[@cobe1mllc]

Right mines are square too

[@ProPayne84]

​@@cobe1mllc I know I'm late late but all the formula for a circle subwoofer is determining is the area of the circle. Formula for determining area of a circle is (r x r) x 3.14. Formula for determining the are of a rectangle or square is Length x Width. Hopefully this helps people ever seeing this in the future.

[@characterflawless1381]

How does the port length play into this when doing a slot port? And what the difference in calculating it between using the wall of the enclosure and having the port splitting between the subs in the middle of the enclosure?

[@RobertJeffersonBased]

To people in the comments: just get the cone area from the speaker specifications. If you're not paying attention to the specifications of the speaker, then stop building and go look.

[@joseceraia]

I ALWAYS HAVE LEARNED TO USE THE THIELE&SMART PARAMETERS

[@mosessalazar7818]

Best video if you are to teach more on how to build and calculate your subwoofer box for a Pacific type of sub would be awesome

[@educated_guess]

for the port area you listed the width and the height, but what about the length of the port?

[@JacobViral2]

Length isn’t a focus for area unless the length reduces the area at certain points, length is for tuning

[@aneelkanhai143]

First viewer I am learning so much man tanks for great video

[@1madmaxx80]

Elementary school geometry, yay!

[@adamhonn8168]

Ive got 2 15s with 6.7 cu ft box with 112 cu in port is that ok?

[@JacobViral2]

Sounds right yes

[@santoshkanhai2083]

I hope the new video will be about max spl

[@JacobViral2]

What you mean max SPL? What terms maybe I can look into.

[@santoshkanhai2083]

@@JacobViral2 i mean what your max db reading will be and sorry if i sad it wrong cause i dont know much about car audio but i like watching your videos (thanks for reply)

[@magicmikebangin15s64]

How dono figure out my dimensions I need for my enclosure is what I'm needing. I have 4 b2 10 inch riots and im trying to figure out how much port I need my opening at top of box is 3.1875 I can work with box is 57.5 long internally and I have 26.25 tall please help. Thank you This is a truck box in my mega cab for reference

[@AlexSammy-pi4gs]

Nice but not accurate

[@stanmondzelewski9253]

So how does cone area equate to port area?

[@JacobViral2]

Depends on the type of enclosure and goals overall. Most do around 40-60% cone area for port area.

[@stanmondzelewski9253]

@@JacobViral2 i got 2 12s. Cone area is 226.08. So roughly 113in² port area?

[@JacobViral2]

@@stanmondzelewski9253 for a 4th order sounds about right yes, could always start little bigger and shrink.

[@stanmondzelewski9253]

@@JacobViral2 what about a regular ported box?

[@JacobViral2]

@@stanmondzelewski9253 14-18sq in. Per cube of box space noticed a lot of designers do.

[@bassnjeep6537]

Isnt 176 the cone area of 1 15" ?? Lol

[@JacobViral2]

Yes

[@Simpleman87]

Thanks for the help. I just got a sundown 18” u series. Let me know if you have any input

[@sathyaarun4695]

not sure ...whts the usage of this number.....Full marty subwoofer for 21" , 10.5X10.5X3.14 = Cone area? Working ports on many build - 64.5 Port Area...% is coming to 18% ..whats that mean then?

[@JacobViral2]

Port area sounds small then?

[@Dying_Breed.300]

So if I needed a box .95 cubic foot net volume with 12.5 square inch of port area and 30.5 port length tuning of 32hz. Now my max width and height of the box is 40.5 wide and 19” high and it needs a bend in the back of the box bottom can be 11” and top 6” it’s for the back of a q5 Audi but I have a baby stroller so we are limited. Please help me it’s a 12” JL tw3-4

[@JacobViral2]

Your already in the right track sounds like

[@doublemanson]

🔴I have a 8 cu ft gross ported box (with 15" kicker L7s 1000w) my port area is 17.5" x 4" equals to 70 in2 (or about 9 in2 per cubic foot). can someone tell me if my port is to small. i heard its supposed to be 12 to 16 inch squared per cu ft

[@JacobViral2]

Sounds a little small, 14-16 inch per cube is a good reference point for ported box, but of course user preference and tuning goals.

[@AKTesla]

For port volume you measured w x h instead of w x l.

[@treylewis10]

Hey I have question regarding this.. I have a box with 1.25 cubic ft and 1 10inch inside what size should the port be?

[@JacobViral2]

I would aim for 20-25sq inches of port.

[@hopskustomaudio]

There are lots of apps out there to download that does all the math for you. All you have to do is plug in the numbers. Much easier imo.

[@RyanBassForLife]

I was never good at math but thanks for the lesson😁

[@1970chevy]

The measurements for the port was high and wight not the length. I'm running a slot port and have no idea how to figure out how to tune it better. The design was free and the box specs seemed close to what would work for my set up.

[@lowhertzhighspl]

Enter all the measurements into a box calculator app

[@bmcdamayne]

So what's a good percentage to aim for in that port area??.. Like 60-85%??

[@JacobViral2]

Depends on the box, tuning goals, SPL/music, etc. to many variables for 1 answer.

[@namegoesherenone6449]

Would love to see a video on this!

[@Simpleman87]

Ok please help. The specs calls for 4 cubic feet air space for my 18 sundown. I am aiming for 32 hurst. My vent is going to be 17.5by3.75. How long dose it need to be so I can add that to my box build

[@JacobViral2]

I would suggest atleast 5 cubes for 18” sub unless you want higher tuned box. Probably gonna need more port area and atleast 25-28” long port.

[@Simpleman87]

I also have original juggernaut before Matts bought it. It’s in a 5 foot box. So for the 18 inch Sundown. If there was 5 foot air space plus speaker displacement and port displacement how big do you think the port should be to get 32 Hz. For the box design that I am building the internal port height is 17.5. How wide and long do you recommend?

[@JacobViral2]

@@Simpleman87 around 5-5.5" width port sounds like it and length depends, use the www.the12volt.com/caraudio/boxcalcs.asp calculator when u get final numbers. Goodluck!

[@Simpleman87]

Thank you for your help

[@hausboxes]

Am I wrong or when you did the 2 12s you didnt multiply by 2

[@JacobViral2]

Ah yea always multiple by sub qty :)

[@quincytrotman2002]

I need help learning how to calculate port height and width for any sub,if u dont mind

[@JacobViral2]

Idk what you're asking? It was explained in the video for port area and subwoofer cone area for any option.

[@pohlcat01]

@@JacobViral2 how did you make the box if you didnt already know what port size you need? how do you calculate to make the design and to cut the boards, i think is what is being asked.

[@sanamachaningombam9906]

Pls tell me how to calculate volume of woofer box with given subwoofer size thanks

[@JacobViral2]

It really depends on the size of the sub and type of sub. I always suggest looking at manufacturing specs suggested for the sub or choice.

[@sanamachaningombam9906]

@@JacobViral2 if you know pls tell me the volume of 4 inch 5 inch n 6 inch subwoofer thanks

[@haydensmith9064]

so i have 2× 15s and a 10" round port does this maths work the same if i use the equation for a 10" sub? i feel like it may be too big so far?

[@haydensmith9064]

its coming up with only 22% though so i must be doing something wrong? anyone care to help? thanks :)

[@JacobViral2]

A 10” aeroport is normal for a pair of 15s. Some run 12”, or 2 8” also.

[@haydensmith9064]

ok thanks for the reply appreciate it. i have a 7.5 cubic foot box and the port is 27.5 inches long with the 2 drivers and cannot seem to find a calculator to get my tune to see if i need to shorten it as all of them only use one driver and that sits me at around 29 hertz does that sound right for 2 still? thanks

[@JacobViral2]

@@haydensmith9064 Your numbers sound right, 28-30hz range for your port 10" and 27~ length with 7.5 cubes. I use google '12volt box calculator' site all the time.

[@haydensmith9064]

thanks good to know 👌

[@74midwestbass74]

VERY NICE INFO BRO!!!

[@michaelmcfarland3519]

What if you have 3 10’s

[@JacobViral2]

Same concept applies

[@notyobiz6207]

question, how do you properly setup subsonic for 4th order? currently tuned to 42 hz. (subsonic on 25 currently)

[@JacobViral2]

I always start with it off and 3/4 volume and visually watch the subwoofer with a sweep and notice the unload frequencies and tune that way. Maybe I can do a video on it soon.

[@notyobiz6207]

@@JacobViral2 ive played that song by dj russticals by taylor swift.. christmas tree i think it's called. 12-25 hz it says and i have yet to see my 4th unload lol.. maybe i don't have enough amp to do it lol (each hd12 has it's own 2k amp)

[@dcaudio1]

How do you know how long to make the port? Your calculating the opening but what about the length?

[@JacobViral2]

Length is for tuning desired as you go longer the tuning lowers.

[@dcaudio1]

@@JacobViral2 I realize that my question is how do you calculate the tuning frequency desired. If i want 35hz how do i calculate the length.

[@JacobViral2]

@@dcaudio1 Now that I always used a box calculator plugin as I don't know that much in depth sorry. Here where I always calculated: www.the12volt.com/caraudio/boxcalcs.asp

[@dcaudio1]

@@JacobViral2 Thats pretty awesome....turns out my math was indeed correct but this makes it lightening fast....thanks Jacob.

[@michaelwielenga8809]

1337

[@astro54541]

Damn dude…. loved this video. Explains a lot why my port is off. Thank you 👌

[@JacobViral2]

Your welcome glad it helped

[@rhurtadorh32]

@@JacobViral2i just finished my sub box for 4 15 american bass elite subs 1200 rms each. My port is 3 inches in width and its 2 feet long. Would that be enough port area? Is it a small slot port?? Its my first time building a box. Thank u

[@JacobViral2]

@@rhurtadorh32 Depends on the port height also before I know. Also size of the cubes in box?

[@rhurtadorh32]

@@JacobViral2 the ports height is 3 inches i gotta get back on you on the cubes. Ill measure it today. Tall long deep

[@JacobViral2]

@@rhurtadorh32 For 4 15" subs, I would go for atleast 16-18 cubes net with atleast 250sq inch of port. With 24x3=72 is too small of port. If more questions mesage me on instagram/facebook JacobViral.

[@youngfeezy7969]

So where would u want ur port area to be if u were doing 2 10s and an aero port?

[@JacobViral2]

Depends on tuning and goals. I would say around 70-90sq in port area so a 8”?

[@alexgarza867]

I planned on doing a 6” port about 10” long. I wanted to have about 6” in the port the rest extended out. Would that be good? For 2 10s

[@alexgarza867]

Jacob Viral2 help😂

[@dragosmarian06]

so for 2x18" what should be the port area?

[@JacobViral2]

Depends on the type of box and goals/tuning.

[@dragosmarian06]

@@JacobViral2 box bass reflex 150litres per sub. Tuned at 30...33 hz

[@mjl6425]

So is 75% efficiency the ideal for a fourth order bandpass box?

[@JacobViral2]

Starting points for bigger ratio 4ths yes ideally but every system varies. Some will do 40-50% others 90% or bigger for burp. Depends on goals rlly and extensive testing.

[@mjl6425]

@@JacobViral2 Gotcha. Now does it matter which way the port is facing inside the box?

[@JacobViral2]

@@mjl6425 No and yes. For cubic space required, ratio, and air flow I would say it varies though.

[@mjl6425]

@@JacobViral2 No I mean wilI I have a loss of bass or cancellation if the port opening is facing the subwoofer? I have 2-12s in a 4th order with the port in the middle facing the subs. I just remember reading somewhere not to do this and I just wanted your take on it.

[@JacobViral2]

@@mjl6425 It's not recommended to have port right near the subs but smaller enclosures usually don't have a choice so you will be fine long as you adjust the length and port area to what works for the music played.

[@arnoldsalazar5851]

Great video man.

[@JacobViral2]

thanks

[@covecityboys]

So 5 8’s would be 51,471?

[@JacobViral2]

4x4x3.14 x 5 = 251.2?

[@covecityboys]

@@JacobViral2 I don’t even remember what the video said or what math i did. Would you be able to refresh me?

[@covecityboys]

@@JacobViral2 I’m watching again now. Maybe I can figure it out. Forgive me for having a brain fart moment I guess…

[@covecityboys]

@@JacobViral2 I am building a box for 5 8” speakers. So would it not be 4r to the 5th power times 3.14?

[@covecityboys]

@@JacobViral2 4x4x4x4x4x3.14=3,215.36? It’s not making sense to me.

[@mattwood413]

Will you plz do a vid on how to use a box building program it’s really confusing

[@JacobViral2]

I wish I could Matt but I don’t design boxes to know sorry. I just built without one personally:

[@mattwood413]

Jacob Viral2 I also thought about that

[@jondoe-pe9ob]

@@JacobViral2 do a video on that then how you personally build sub boxes it can help a lot of people out and ik cuz it can help me out

[@jondoe-pe9ob]

Hey Jacob if I have a 1 18 that specs are 5.25 cubic feet and 78in port area but I want low bass so I wanna tune the box to 29 hz how big should I make the box and do I still use 78in port area or is there a recommended square inch per cubic foot?

[@mattwood413]

jon doe what I did was build the box to fit the back of my suv you can always tune down if you have to I’ve been told by a few different ppl to build it bigger because you can always make it smaller but it’s harder to add to it if you build to small if that makes sense I’m not no box builder just trying to help ya out with what worked for me good luck bass brother

[@fuckendave7700]

How did you determine the port area? How did you decide to go with 14x4.25 and not 14x2 or whatever?

[@JacobViral2]

Port area to cone area ratio. I wanted a small ratio difference so started big and shrink to loudest and that was it.