Need help designing a round enclosure

[Subless]

Hi, first post.

I have a Jeep JK Unlimited with little space for a subwoofer unless I want to

use up cargo space and I really don't. There is a sub build by JL that is a custom fit over the

wheel wells. - JL Audio Stealthbox® (Black, Driver's Side) Custom-fit fiberglass enclosure with one 10TW1v3-4 subwoofer — fits 2007-up Jeep Wrangler Unlimited at Crutchfield.com

$600 - I don't want to spend that much. I'd like to build a round enclosure maybe sonotube that would fit in the same area.

JL makes a shallow driver -

http://www.amazon.com/10TW1-4-Audio-300W-4-Ohm-Subwoofer/dp/B00OALB31A/ref=sr_1_1?ie=UTF8&qid=1460588614&sr=8-1&keywords=10TW1-4 which is SVC 300w RMS @4ohms

The amp I'm looking at puts out 340w rms @4ohms and 600w @2 ohms

so I thought I'd build two of these and wire in parallel for final 2 ohm impedance and each driver getting 300 watts each @2ohms. Sound right?

They show a rectangular sealed design for this driver - 16.125 in x 14 x 5.25 deep. Can I make a round enclosure for it that would work ? I'm not quite sure yet how I'd mount it, but a 12" wide tube I'm thinking could fit this 10" driver. I'm concerned that if I'm supposed to match the volume of the rectangle above, then this tube might end up being too deep. I didn't really want to go more than about 8".

Thanks to any guru's who might have a clue on this one.

Thoughts?

Click to read more...

 

[Subless]

Checking the specs for this sub, I calculated that the total volume of the suggested box is about 1185 cubic inches at 16.125 x 14 x 5.25", but

actually it would be less by a factor of 3/4" wall thickness which should be about 14.625 x 12.5 x 3.75 = 685 cubic inches.

In order to achieve that in a 12" diameter tube, it would have to be at least 6" long and probably more like 7 due to thickness of

the tube walls and then adding 1.5" to the tube length for each of teh 3/4" ends of msb or whatever, so 8.5".

I just measured for 14" diameter concrete tube above the wheel well and I think that will also work.

Not counting the thickness of the walls of the tube, the volume is 3.14 x 7 x 7 = 154 square inches per 14" diameter.

685 / 154 = 4.45" for length of tube and it would be probably more like 5.5" if

I took into account the wall thickness and finally 7" if I add the top and bottom 3/4". But that seems doable.

Wondering if anyone knows how to strengthen a tube? - fiberglass?

Any other means that's not as messy or potentially lumpy? Sheet metal wrapped and glued/screwed around it?

 

[The_Quiet_One 10+ year member]

Is there a particular reason you want a circular enclosure over a rectangular box with a wedge taken out for the wheel well? I'm not familiar with your vehicle. Will the round enclosure really help you save space?

 

[Boomin_tahoe 5,000+ posts]

Interesting....how would you make a round enclosure?! I've yet to see one.

I've just about seen every other shape.

OP...post up a pic of the area where you want the sub mounted at. Chances are, a custom one will need to be build to accomodate that area.

 

[blazian87 10+ year member]

Yea I've seen people make an enclosure with cylinders before. I saw one made with a keg barrel on youtube. Pretty cool stuff. I think putting it in your spare tire well area is the best place to put it if you wanna save space. You can make a false floor and have a sub hole cutout just right above the spare wheel opening. Then make a custom fiberglass enclosure underneath it. I'm sure you can fit a regular sized 12" sub under there but you should check measurements just in case. Using a tube under there can work too but you can utilize more airspace if you fiberglass it all the way to the edges. Definitely alot more work involved. Sonotube makes it simpler. You can use sound deadener around the tube to strengthen the tube walls. Whatever works for you man. Either way can work. Best of luck to you OP.

Sent from my iPhone using Tapatalk

 

[blazian87 10+ year member]

Wait a min, do you even have an opening underneath when you lift up the trunk matt? If not then using a cylinder will probably not save you much space over a rectangular box or custom fiberglass. I would also imagine a cylinder enclosure would be rolling all over the place every time u make turns lol.

Sent from my iPhone using Tapatalk

 

[Subless]

I didn't think that I'd be able to make a form fitting enclosure look very good. I've seen videos of custom fiber enclosures to try to replicate what JL Audio did for that custom sub I posted above. I thought that if I could figure out how to mount a round one, at least the bulk of the unit would be purchased complete. I think for mounting, I'd have to run a metal circular band around the side closest to the window and fasten it using two of the bolts that hold on the hard top. Then have one metal foot/strap on the inside edge bolted into the side of the wheel well.

Has anyone considered using a floor tom? I used to be a drummer, so that enclosure came to mind. I also found this drum shell to be interesting - Keller Covered Grade 5 Ply Drum Shell 14" x 8" Dia | eBay

It is after all made for sound. Even a finished drum in the right size could be very interesting since the ends are meant to be bolted in tight. Problem with that idea is finding two identical drums that were in good condition that didn't cost a fortune. Maybe just the shell is the best idea.

Here's a drumshell in acrylic - Brand New 14"x6" Solid White 8mm Thickness Acrylic Snare Drum Shell | eBay

wonder if that material could be used.

Here's straight from the factory - http://www.precisiondrum.com/html/shells.html

This is interesting with the reinforced ends

http://www.precisiondrum.com/html/body_shells.html#mahoganshells

Could use one of their wraps to spiff up the look - I wouldn't want it to look like a drum, so I'd probably choose solid black or chrome

http://www.precisiondrum.com/html/body_wrap.html#pearls

Then I got to thinking that just adding a drum wrap to a sonotube would give it extra strength

and also make it look cool and professionally built. That might be the economical way to go.

 

[blazian87 10+ year member]

I didn't think that I'd be able to make a form fitting enclosure look very good. I've seen videos of custom fiber enclosures to try to replicate what JL Audio did for that custom sub I posted above. I thought that if I could figure out how to mount a round one, at least the bulk of the unit would be purchased complete. I think for mounting, I'd have to run a metal circular band around the side closest to the window and fasten it using two of the bolts that hold on the hard top. Then have one metal foot/strap on the inside edge bolted into the side of the wheel well. Has anyone considered using a floor tom? I used to be a drummer, so that enclosure came to mind. I also found this drum shell to be interesting - Keller Covered Grade 5 Ply Drum Shell 14" x 8" Dia | eBay

It is after all made for sound. Even a finished drum in the right size could be very interesting since the ends are meant to be bolted in tight. Problem with that idea is finding two identical drums that were in good condition that didn't cost a fortune. Maybe just the shell is the best idea.

Here's a drumshell in acrylic - Brand New 14"x6" Solid White 8mm Thickness Acrylic Snare Drum Shell | eBay

wonder if that material could be used.

Hmm.. That is pretty interesting. I bet it would sound good in that. Did you figure out where you wanna put this enclosure? You said that space was an issue. Are you trying to keep it as stealth as possible? or are you just gonna put it in the corner somewhere?

 

[Subless]

Hmm.. That is pretty interesting. I bet it would sound good in that. Did you figure out where you wanna put this enclosure? You said that space was an issue. Are you trying to keep it as stealth as possible? or are you just gonna put it in the corner somewhere?

I want to put it essentially on top of the wheel well. It won't form fit to it, but done right it could look like just natural round speakers in that location. If I can keep the length of the tube less than 8", it won't encroach on cargo space. I will get rid of the stock 8" sub enclosure and actually free up some space. At least that's the idea; execution may be an entirely different matter. I'll see if I can get a photo to help illustrate. I cut out a very rough 14" circle of cardboard and held it in place last night where I want the enclosure to go. The real trick to this is going to be the mounting. This company might come in handy. I virtually stumbled onto them - OEM Brackets-L Bracket Cost is everything though. If I can't keep the cost down, then I might as well buy the $600 JL Audio rig.

It's interesting that the drum company can do custom wraps, so naturally I starting thinking of black with silver Rubicon lettering. Then my imagation went a little further and I thought it would be nice that these strap/brackets could be the color of my Jeep (glossy dark cherry). Found this url in a post about the Rubicon font - pixeldecals.com. They could supply the artwork to the drum company - again, depending on cost; otherwise I'd just get the straight black wrap. I would like to end up with some kind of an on purpose, oem look about it though. I attached a photo so that you can see the Rubicon font on the hood.

 

[Subless]

Here's a couple pics of where it would go. This quickly cut out cardboard is not perfectly round but is close enough to 14" diameter.

The tape measure shot is showing the target 8" depth. The seatbelts are a little bit in the way, but I can install another one of those "C" belt guides if necessary to move them out of the way. You can see the two bolts holding the white cab top on. I'm hoping to be able to fasten a bracket on there and then drill one hole near the side bottom of the wheel well to attach a support bracket to the other side.

I snagged the set back shot from the internet and drew the red circle showing where the speaker will go.

 

[Subless]

...

 

[Subless]

Interesting....how would you make a round enclosure?! I've yet to see one.I've just about seen every other shape.

OP...post up a pic of the area where you want the sub mounted at. Chances are, a custom one will need to be build to accomodate that area.

Pardon, I didn't really mean round as in a ball, but cylindrical like Sonotube.

 

[Subless]

Yea I've seen people make an enclosure with cylinders before. I saw one made with a keg barrel on youtube. Pretty cool stuff. I think putting it in your spare tire well area is the best place to put it if you wanna save space. You can make a false floor and have a sub hole cutout just right above the spare wheel opening. Then make a custom fiberglass enclosure underneath it. I'm sure you can fit a regular sized 12" sub under there but you should check measurements just in case. Using a tube under there can work too but you can utilize more airspace if you fiberglass it all the way to the edges. Definitely alot more work involved. Sonotube makes it simpler. You can use sound deadener around the tube to strengthen the tube walls. Whatever works for you man. Either way can work. Best of luck to you OP.

Sent from my iPhone using Tapatalk

I'm hoping for an easier and cleaner solution with a Sonotube approach vs fiberglass. What type of sound deadener would stiffen up the walls? You mean like one of the spray ons? Not a dynamat type product, right?

 

[Subless]

Wait a min, do you even have an opening underneath when you lift up the trunk matt? If not then using a cylinder will probably not save you much space over a rectangular box or custom fiberglass. I would also imagine a cylinder enclosure would be rolling all over the place every time u make turns lol.

Sent from my iPhone using Tapatalk

Photos help. See the ones I attached. I'm talking about mounting cylindrical enclosures horizontally above the wheel wells. These won't be very long; maybe 8" so it cannot be a ported sub. It has to be totally enclosed to be that small according to PL audio specs.

 

[Subless]

I constructed this fake 14" x 9" deep tube to show where I want this to go.

I really don't want it any deeper than 8", but I made it 9" to see if it might

be tolerable.

View attachment 26554749View attachment 26554750