# Subwoofer Advice.



## Acetaminophen (Mar 1, 2010)

I just bought the JBL 3501 amp, got a nice deal on it.
Anyway, I have been looking around and have seen a few subs that catch my eye.
These are the subwoofers I have been having my eye on.

Infinity 1260w
Polk Audio db1212 (The 1240 in a sealed enclosure)
JBL GTO1214D
Polk Audio MM1040D
JVC Arsenal CS-AW6240
Rockford Fosgate P3D410

I want opinions on these subs, who has owned them, have they done well...
Any other recommendations?
I am open for options....budget is $200 for a sub. (Anyone have the cheapest price?)
WHat opinions do we have?
Thanks so much.
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## pharoah (Aug 28, 2006)

the jl audio 10w1 is in your price range and is a very capable speaker.


here is a deal a memphis audio 15 inch for 109$ look below it they have deals on speaker boxes as well.


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## Acetaminophen (Mar 1, 2010)

15 inch seems a bit much...doesn't seem to be accurate either. 
The JL audio? Never had JL, are the clean and loud? 
Thanks.


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## pharoah (Aug 28, 2006)

yeah jl makes awesome speakers.i got a memphis just like that but its a 10.i also got a jl audio that size.they are both very good speakers.


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## Acetaminophen (Mar 1, 2010)

I was going to get the Polk audio DB1212, would that JL out perform the Polk Subwoofer?
Thanks.


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## pharoah (Aug 28, 2006)

dunno i have never heard that polk before.

i seen this on another post you started.

I have been doing some research on some sound deadening, I just put an cat back exhaust it's a flow master thunder series...on my truck

if you go with the polk you better be sure it can fit in you truck.that jl i listed is a wedge style box made to fit behind truck seats.


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## Acetaminophen (Mar 1, 2010)

It's has room, seats in the back...extended cab. The subwoofer can fit between the two seats. I had a dual box in there before and it fit all right.


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## Acetaminophen (Mar 1, 2010)

I am going with the JBL GTO1214D any accurate blueprints on how to build a custom ported box? 
I see diagrams on their website...but no specific instructions.


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## pharoah (Aug 28, 2006)

you can use a program like winisd to design a box.


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## Acetaminophen (Mar 1, 2010)

I would just put in the port size, all the subwoofer info and then print out the sub diagrams?
Thanks alot.


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## Acetaminophen (Mar 1, 2010)

I put in all the information...and I do not see how I make a box from it....of course I have no carpenter skills so maybe that is why? 
I just see numbers and lots of them....
Thanks.


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## pharoah (Aug 28, 2006)

let me ask what is more important here.sound quality?,or quantity?

sealed enclosure will provide tighter bass,but not play quite as loud.

ported enclosure will not be quite as accurate in reproduction,but will play louder.

keep in mind a sealed enclosure will play plenty deep for music.also a sealed enclosure is so much easier to get right.where as the ported enclosure is alot more difficult to tune properly.

YouTube - Car Audio Subwoofer Enclosure Design and Fabrication


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## Acetaminophen (Mar 1, 2010)

Ah, well. I want a little of both. That is why I was reccomended ported enclosure because it will give me a 3-6 db gain over a sealed and I will not lose that much accuracy. 

I can';t seemto find how to get my cut outs or anything....


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## pharoah (Aug 28, 2006)

well for the speaker cutout you need to mark the your front baffle.the cutout diameter for the speaker.use something like a jigsaw to cut the hole out.now if you want to be really picky about it.you will also need to know things like.the space the speaker itself will take up inside the box,and adjust the volume accordingly.now the recommended box size i seen listed at crutchfield was 1.75 cuft.it said to port that box with a 4inch diameter,by 10 inch long port tube.

so here look at this pic .the speaker mounted on the front and the port tube on the top.you can lay that down,and it would be the side.the dimensions listed are external dimensions.using 3/4 inch mdf.


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## SABL (Jul 4, 2008)

All I can say is that there are many ways you can build a simple box. Please note that MDF stands for Medium Density Fiberboard....*it is not your run of the mill particle board* and not even close to OS (Oriented Strand). 

How do you plan on cutting the material?? The pieces will need to be accurate and tight fitting. Assembly....what kind of fasteners will you be using?? 

The easiest way is to butt the pieces together....unless you want to try and flush up the back. Let's go the easy way:

Front & Back= 16 1/8" X 25"
Sides= 8 3/4" X 25"
Top & Bottom = 8 3/4" X 14 5/8"

Top and bottom fit between the sides...... the front and back lays completely over the face and rear of the box. 

*I can get the dimensions closer, depending on the skill of the fabricator. Didn't know if 1/16ths were too intimidating so I stayed with 1/8" increments.


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## Acetaminophen (Mar 1, 2010)

My father will be building this with me, and he has some very high end tools to do the job. Plenty of Craftsman saws, and table saws. He has the works. He build my front deck for me. Between the two of us I am sure we can get it fairly accurate. 

As for fasteners....I was told drywall screws are best because they have a closer thread and are thinner.
What would you guys recommend. I will use whichever is best. I know to pre-drill holes by the way....

And this box you provided would be with the 10 inch by 4 inch port? 

How would I make the port? Would I just buy a plastic one?

Thanks so much.


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## pharoah (Aug 28, 2006)

pharoah said:


> well for the speaker cutout you need to mark the your front baffle.the cutout diameter for the speaker.use something like a jigsaw to cut the hole out.now if you want to be really picky about it.you will also need to know things like.the space the speaker itself will take up inside the box,and adjust the volume accordingly.now the recommended box size i seen listed at crutchfield was 1.75 cuft.it said to port that box with a 4inch diameter,by 10 inch long port tube.
> 
> so here look at this pic .the speaker mounted on the front and the port tube on the top.you can lay that down,and it would be the side.the dimensions listed are external dimensions.using 3/4 inch mdf.



what i posted there with pic is the exact size your box needs to be with port.


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## SABL (Jul 4, 2008)

With the available tools you should have no problem. There are two types of DW screws... fine thread and coarse thread. We use the coarse thread for wood applications. With MDF you may need to test the size of the pilot hole on a few scrap pieces to make sure the piece you are screwing into doesn't bulge or split. MDF is very unfriendly when fasteners are driven into the edges...even nails can cause a split if driven in too close to the end of the piece. Stay away from the ends by at least 2". 

Pharoah will need to give advice on the port.....I have no clue. I'm just a retired carpenter who, at one time, did have a decent sound system til the kids ransacked it and took the components to their rooms for _their_ enjoyment. I got tired of refishing the cables and hooking everything back up. 

I'll check back but I think pharoah will give you some good tips.


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## pharoah (Aug 28, 2006)

one more small thing id like to point out.that speaker has a fairly long mounting depth.id cut the speaker hole first,and make sure!where ever your going to mount the port it wont run into the speaker.

edit: you need to be very sure the box is leaking no air from anywhere except out the port.that is very critical for sound quality.id go as far to wood glue all the seems to make a very nice air tight seal.


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## Acetaminophen (Mar 1, 2010)

Do not worry. I will seal the crap out of the box. Any area that could leak I will seal it from the inside with silicone or the some "Seal All" expensive but works like a charm. 

As for the port. Pharoah, you have it on the top...that would mean that I should put it towards the back of the subwoofer....any reason why you put it on the top? Just curious. 
What would be the best way to strengthen the box and brace it so that it is as strong as it can be with out over kill? 
Thanks for all the help.

Also, I only have a Lowes....they will carry MDF board? (better alternative??)


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## Acetaminophen (Mar 1, 2010)

I have found the port. 
I will cut it to be roughly 10 inches long front to back....

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=268-352&vReviewShow=1

What do you guys think? Will this be a good port or not?
Thanks.


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## SABL (Jul 4, 2008)

Pharoah would know more about accoustical properties of different materials. Lowes may have MDF but particle board is more forgiving in accepting fasteners....and it's cheaper. IMO the only reason to use MDF is if the unit is going to be painted....MDF is much smoother. I don't know if adding bracing to the box will affect the sound qualities....the size of the box and use of 3/4" material is equivalent to the floor in most houses. The only question I would have is if the port would need a "stand-off" bracket (on the far end) to keep it in place if the unit is placed on it's side. 

For sealing, a small bead of silicone will work...or even polyurethane based construction adhesive (my preference) will work just fine. Don't over-do it...more is not better. You want just enough to make a solid seal...if it squeezes out and makes a huge mess you need to cut back.


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## SABL (Jul 4, 2008)

After looking at the port, you will not need any bracing to support it.....it has a mounting flange.


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## Acetaminophen (Mar 1, 2010)

True. Less is usually more when it comes to installing stuff....I have figured that out. You are right though, I would prefer a construction adhesive over silicone just for that better seal and added strength. 

I was thinking of actually sanding it all down, giving it some primer and spraying it with some of that bed liner. It looks fairly nice and I have heard it had deadening qualities....to maybe help with acoustics?
I am not sure. I guess lets see what Pharoah thinks.


So I have looked at videos and have decided that it shouldn't be too terribly hard to do, I just have to be precise and take my time.

I will run to Lowes tomorrow and see what they have for boards and do a price check.


http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-292

Terminal Cup. That should do it aside from the boards and the Bracing....


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## pharoah (Aug 28, 2006)

that port will be just fine.the terminal cup is also good.parts express is a legit place just so you know.i have several things from there.

internal bracing will affect sound quality for the better.it will reduce the boxes resonance.


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## Acetaminophen (Mar 1, 2010)

So, should I just add some of the scrap wood as my bracing like a 2 or 3 inch length brace every couple of inches (The left overs from my cut outs) ....or how should I brace it? 
I was thinking some cross bracing...every 4 or 5 inches....any counter suggestions?
Kind of looking for the best way to do it without taking up to much space. Should the dimensions of the box stay the same? I was wondering about all that bracing I would do...I don't want it to mess with the sound (For the worst)....
Thanks.

As for PartsExpress, I did know. I have bought wire from them, and speaker cable.


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## pharoah (Aug 28, 2006)

you could brace that way yes.i have a home stereo sub box that is braced like that.


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## Acetaminophen (Mar 1, 2010)

Okay. So, you calculated the port tube, and the subwoofer. The box volume came out to roughly 1.75. With the measurements rounded up would that give me enough extra so that I could brace the box and not worry about it dropping to far below the 1.75? 
Should the box be a bit bigger or will it be fine?

Also, if I use a solvent let it cure for at least 24 hours so that it does not eat my sub? 
While bracing did you use tiny screws or just glue? 
Thanks.


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## SABL (Jul 4, 2008)

That's the question I had......the box size has been calculated for cu ft and adding bracing will decrease the inside volume (capacity, not Db). I was thinking a few more pieces the size of the top/bottom will be an exact fit for braces.....but you will need to ventilate (cut holes in them) or you just built a small box inside of a bigger box. Pharoah will know more about this but I was thinking of offsetting the speaker and using one brace in the center.


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## Acetaminophen (Mar 1, 2010)

I was thinking either cross braces every few inches or a brace behind the subwoofer with a huge hole in it, and another hole to stabilize the port maybe....


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## pharoah (Aug 28, 2006)

depending on how much bracing you add.you will need to calculate volume of the braces themselves.throw the box volume off to far it will change the tuning frequency.

look at that video i posted again.specifically the part about bracing.


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## Acetaminophen (Mar 1, 2010)

I got it. Yeah....I will just adjust the box dimensions slightly to give me the 1.75.
I think I have it down now. Just will need to figure out exactly how much bracing I would want.... 
I suppose that I should make a mock box with some card board or some cheap wood... to figure out the bracing I would want....that way I would know what I am doing.
The rest would just be estimate from there I suppose....

Oh and lowes has a 4'x8' boaerd of MDF 3/4 that should cover me....for about 30.50...the port was 12... and the terminal was 6. Then supplies. So, it should come out roughly around 75 for the build that is not to bad at all...


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## pharoah (Aug 28, 2006)

a working model is a fantastic idea.:woot:


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## SABL (Jul 4, 2008)

I did get around to watching the vid....:grin:..What I had in mind was a single shelf brace as mentioned in the vid tutorial. Air nailer would be nice....does your father have one?? I have 5 or 6 of them in my garage....:grin:..What the peeps in the vid seemed to be using was a 2" brad nailer which uses much thinner fasteners. 

Be careful with the amount of MDF you use for bracing..... I would only use it for the "shelf" type and use a single brace. 3/4" MDF weighs roughly 3.6 lbs per sq ft if the last shipping ticket I looked at is correct....180lbs for a 5' X 10' sheet. Thinner MDF braces will have a tendency to split if you try to use mechanical fasteners and solid wood is recommended in that case.


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## Acetaminophen (Mar 1, 2010)

No nail gun. My father is does most work by hand(Exept screws....he uses a drill) 
But nails, he has a nice hammer....could that work just as well just hammering them in there? Nails or screws....?
I still have a few weeks before I buy this subwoofer so I wouldn't mind getting all the kinks out of it before hand you know?
Thanks for being patent. I am a very thorough type of person.


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## pharoah (Aug 28, 2006)

ive seen nails ,and screws in speaker boxes.so use either if ya go screws just be careful not to split out the sides.as far as being very thorough you should be when building a subwoofer.especially if you want it to sound proper.


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## SABL (Jul 4, 2008)

So far you're doing great in giving thought to your project. As for nails, you may be able to use 6d CCS (6 penny Cement Coated Sinkers) but run the risk of splitting the MDF. A nail gun is superior in this application because it gets the job done with one hit and the fasteners are far thinner than anything you can drive in by hand. I'm trying to think when the last time was that I actually used a hammer....:laugh:.. 

Use what will work....you will not be using a great quantity of fasteners. Trust the adhesive (especially if it is polyurethane construction adhesive)....the fasteners only hold the pieces together until the adhesive sets. 

If your father has a compressor, check out the power nailers when you are in Lowes. They do have a 2" brad nailer for $70...and if he likes to tinker and build things, it will be a good addition to his toolbox. (And you can borrow it to experiment on building various speaker boxes....:grin


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## Acetaminophen (Mar 1, 2010)

Yeah. Maybe someone I know has a nail gun....if not I guess I will have to fine some thin nails....
No big deal. I will poke around lowes tomorrow and see what they have. Pick up some adhesive and such...start collecting supplies.
I have been looking at other builds and it seems that cross bracing is the most popular but the 1 middle brace with the holes in it seems to be the sturdiest for the amount of space it takes up. 

I will try to pick up some cheap wood and do a mock build up. 
Not sure when I will have time though


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## lcurle (Oct 5, 2008)

I just glue the edges, brad it in place, once dry, silicon the inside and FG resin the outside, then add my braces to the inside, usually cut in a wedge shape, but to each their own. I use silicon around the cup before I seat them, and my ports are usually built into the box either slot or L depending on the Hz I want it tuned to.


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## Acetaminophen (Mar 1, 2010)

I think it recommended not to use l ports. I cannot remember. 
Thanks, how much bracing did you use....just one on each side?


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## pharoah (Aug 28, 2006)

we want pics of the finished product,or we are sending the subwoofer police.:laugh: just kidding


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## Acetaminophen (Mar 1, 2010)

Here is what I have now. 
As soon as I get my new car or vehicle. I will buy new subs, and new fronts/backs. 

















Disregard cap in the subwoofer picture that was before I moved everything. 
I have the Kenwood Excelon x494 unit as well

*

Also. for those of you who know not what snow is or what salt can do...these pics are why I am buying a new car and are the better of the damage. Sorry for the long post and the lengthy pictures. *


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