Box plans?

[Warpdrv]

Couldn't one effectively use 2 - 4" ports at a shorter length as well....

 

[annunaki]

Couldn't one effectively use 2 - 4" ports at a shorter length as well....

No way!!

As port surface area increases so does port length. Two 3" ports have a surface area of 14.14"^2. A single 4" port has a surface area of 12.56"^2. Two 4" ports would have a surface area of 25.12"^2. It is a significant difference. The length would go from 20" on a single 4" to probably close to 40"+ with dual 4" ports.

 

[Sniperslayer]

what do u guys think about using these plans for the first box he has here:

http://forums.soundandvisionmag.com/audiovideo/board/message?board.id=57&message.id=4342&query.id=2414#M4342

if this is good enough i would be happy to go with that because of all the dimensions are there etc. otherwise i'm going to have a very hard time designing my own

 

[Warpdrv]

No way!!

As port surface area increases so does port length. Two 3" ports have a surface area of 14.14"^2. A single 4" port has a surface area of 12.56"^2. Two 4" ports would have a surface area of 25.12"^2. It is a significant difference. The length would go from 20" on a single 4" to probably close to 40"+ with dual 4" ports.

Well Im glad to know that info... I had no idea...
Still haven't put my project into motion yet either....

 

[annunaki]

Those plans are fine, but that is not for your sub. They were designed around the Dayton Titanic MkIII.

With a little patience, it is not hard to figure out an enclosure. If you tell me the dimensions you want it to fit, (your maximum acceptable dimensions for Height, Width, and Depth) I can design the enclosure for you and tell you what cuts of MDF you will need. Unless I get instructions on how to do up a diagram on the computer, that is all I can get for you. Although, I could draw up some plans for you as well and scan them.

 

[Sniperslayer]

^ would you say it's best to go with those ones from CSS?

i'm kinda leaning towards going with the big box now, as the plans and cuts are all there

 

[annunaki]

^ would you say it's best to go with those ones from CSS?

i'm kinda leaning towards going with the big box now, as the plans and cuts are all there

The plans from CSS are not bad. I would probably do the bracing a bit different but they are decent. You can get similar performance out of a bit smaller enclosure like suggested though. However, the bigger enclosure should be a bit more efficient and allow the sub to play a bit deeper.

 

[Sniperslayer]

the only problem is i have to extend it even more to acomadate the amp..but i guess i could perhaps make it smaller and still acomadate the amp? would it be ok to just make it shorter, or keep the same but make space within the box for the amp?

 

[annunaki]

Essentially what you can do is just make the enclosure a bit longer on whichever plane it is you wish to mount it. How much depth does the amplifier require? What amount of air does it require for proper ventilation?

For instance, say the enclosure is to be 16 x 18 x 22 and you want to mount the amplifer on the rear of the enclosure on the other 16 x 18 panel. Say the amplifier is 3" deep and requires another inch for ventilation. Simply make the panels a bit longer to accomodate the amplifier. So all said and done the enclosure is now 16 x 18 x 26. Internally the box is still the same size for the subwoofer. All you really did was add another enclosure on the back for the amplifier. You could even vent this if you wanted for better cooling.

It does not have to be hard unless you want it to be.

 

[Sniperslayer]

K..i've started my build! [pics/build thread will be up soon]

but a couple questions first

are screws a no-no? last time I built my sub box for my car i used glue + screws, then sealed the inside and outside seams, which worked unbelivably the box was sooo solid and sounded awsome, so i'm considering doing the same thing with this box, i will be using a countersink then most likely putty over them before painting the box

2nd, would you guys recomend any sort of inner lining? on the plans it says recomend to line the walls with fibreglass, wool felt, or polly batting

 

[annunaki]

Sniper,

Definitely use screws. Use a good wood glue. Elmer's and Tite-bond are very good. The screws are mainly there to hold the enclosure together until the glue sets. They do help to hold it together as well. Make sure to pre-drill all of your holes. I usually recommend counter-sinking as well so the holes can be filled with wood putty. Depending upon how the enclosure is finished, this step can be optional (filling countersunk holes). As far as the interior is concerned, lining is optional. Usually, ported enclosures are not lined with anything. If you must and or want to, poly-batting spray glued to the inner walls should be fine. A few staples to hold it in place would help as well.

K..i've started my build! [pics/build thread will be up soon]

but a couple questions first

are screws a no-no? last time I built my sub box for my car i used glue + screws, then sealed the inside and outside seams, which worked unbelivably the box was sooo solid and sounded awsome, so i'm considering doing the same thing with this box, i will be using a countersink then most likely putty over them before painting the box

2nd, would you guys recomend any sort of inner lining? on the plans it says recomend to line the walls with fibreglass, wool felt, or polly batting

 

[Sniperslayer]

kk, i've completed the inner and outer baffles, and will start assembling the box tom, pics to come

 

[annunaki]

Good luck. I hope everything goes well and smooth for you.

 

[dem beats]

Sniper,

Definitely use screws. Use a good wood glue. Elmer's and Tite-bond are very good. The screws are mainly there to hold the enclosure together until the glue sets. They do help to hold it together as well. Make sure to pre-drill all of your holes. I usually recommend counter-sinking as well so the holes can be filled with wood putty. Depending upon how the enclosure is finished, this step can be optional (filling countersunk holes). As far as the interior is concerned, lining is optional. Usually, ported enclosures are not lined with anything. If you must and or want to, poly-batting spray glued to the inner walls should be fine. A few staples to hold it in place would help as well.

A few tips to expand on this... Screws are the weak point in a sub box. They help yes, but in moderation. I would saw less is more, many guys just use brads to hold together as the glue sets, for aplications with low watts like yours.

Also use WOOD glue. MDF is wood dust and wood glue, using wood glue will make it more like one solid peice of board, which is the ultimate goal.

You also asked about Glassing... well here is my opinion, your set up isn't going to be flexing the box tooo much and certianly won't be causing that much pressure. Something more important is glue glue glue and more glue. especialy if you used a circle saw and not a table saw for the cuts.

If you do a flared square(aka flared slot port) then you may want to toss down some kitty hair and glass it up, otherwise nothing else is needed using 3/4 MDF board and plenty of glue with air tight seals you will be more than fine sir. If you were going to go up into the 1,000 pluss watt range etc, then it may be worth it, but even then doubling up on the MDF would be a better option IMHO.

 

[annunaki]

A few tips to expand on this... Screws are the weak point in a sub box. They help yes, but in moderation. I would saw less is more, many guys just use brads to hold together as the glue sets, for aplications with low watts like yours.

Also use WOOD glue. MDF is wood dust and wood glue, using wood glue will make it more like one solid peice of board, which is the ultimate goal.

You also asked about Glassing... well here is my opinion, your set up isn't going to be flexing the box tooo much and certianly won't be causing that much pressure. Something more important is glue glue glue and more glue. especialy if you used a circle saw and not a table saw for the cuts.

If you do a flared square(aka flared slot port) then you may want to toss down some kitty hair and glass it up, otherwise nothing else is needed using 3/4 MDF board and plenty of glue with air tight seals you will be more than fine sir. If you were going to go up into the 1,000 pluss watt range etc, then it may be worth it, but even then doubling up on the MDF would be a better option IMHO.

I agree on the screw part. Usually one screw every 4 inches will allow for a good bond without usuing too many. Wood glue is definitely where it's at. It bonds the two pieces of MDF together as one.

If a person is not using a table saw for nice smooth cuts, I would actually suggest something like a PL-200 sub flooring adhesive. It forms a very strong bond, almost as good as wood glue, but fills in the gaps that may have occured during cutting.

 

[Sniperslayer]

one last thing in terms of the design if you may,

if u guys could refer back to the CSS plans there on the previous pages, or here:

http://www.creativesound.ca/pdf/SubDuction-plans-290307.pdf

for the middle plan, the one i'm using, all those holes in the bracing, is there a different way i should go about those?

i mean it says just to make them random so i'm asuming thats to try and make as much air flow as possible? so should i just grab my drill and start drilling holes in all the bracing as pictured?

 

[annunaki]

one last thing in terms of the design if you may,

if u guys could refer back to the CSS plans there on the previous pages, or here:

http://www.creativesound.ca/pdf/SubDuction-plans-290307.pdf

for the middle plan, the one i'm using, all those holes in the bracing, is there a different way i should go about those?

i mean it says just to make them random so i'm asuming thats to try and make as much air flow as possible? so should i just grab my drill and start drilling holes in all the bracing as pictured?

Here is what I have done for bracing in the past. It leaves a lot more open airflow inside the enclosure. Granted mine was a sealed enclosure but the technique can still be applied to vented enclosures. To me it would take a lot less time too. I did all of mine with a jig saw. Just take your time and you can make nice smooth cuts. I want a router before any new projects though.

 

[Sniperslayer]

I cant really see myself using somthing like that in my box though, i wouldnt even know where to start?

is the bottom line just getting as much airflow as possible? ie. if i follow through with the bracing as it is in the plans, and just drill a tonne of holes, will there be any problems?

also, do hole sizes matter? or if i just drill enough is that good enough?

 

[annunaki]

What I am trying to get across is that the holes don't have to be round. They can be large openings. Just be sure there is enough material left to screw into and to keep the brace strong.

 

[Sniperslayer]

What I am trying to get across is that the holes don't have to be round. They can be large openings. Just be sure there is enough material left to screw into and to keep the brace strong.

lol and thats what i was trying to ask, so just a misunderstanding hehe