Design for Tuans Custom 15" sub thats going to get 3800rms Daily from a T30001bd

[SHiZNiLTi 10+ year member]

So I just bought this HUGE 15" sub with a superior 3 points of cooling and a 4" Coil that will take 3-4k rms daily very easily. This is absolutely not a production model sub (yet) and costs a whole lot to build. It's extremely heavy and has very good motor strength.

Pics simply don't do it justice....

Anyways I need to get a box made by Friday night.

I'm thinking about doing a CRX style box around 4 cuft tuned to 38hz.

This is what I've come up with so far...

4.5 cuft tuned at 38hz with 81sq.in. of port area:

box: 34" wide x 24" deep x 15" tall

port: 32.5" wide x 2.5" tall

I'm going to use resin and half a PVC pipe as a form to make a perfectly round smooth corner in the corner of the box where the back of the port is. Hopefully this will cut down on any type of port noise that may be caused by the small height of the port that is only 2.5" tall. I'm also going roundover with my router every edge that need it.

Please give me any ideas on a design that you think will be good for this sub.

BTW it's going into the blazer in my sig.

Click to read more...

 

[lilmaniac2 5,000+ posts]

any more pics?

 

[60ndown 10+ year member]

few braces and your good 2 go.

 

[SHiZNiLTi 10+ year member]

No more pics as of now, but the sub should be here this Friday and I will take a bunch of really hi-detail shots then.

Ok so back to critiquing this design....

There's a few issues that I'd like some feedback on.

1: Im at 81sq.in. of port area. Is this too much for my sub in this 4.5 cuft box? I allways thought you should do 12sq.in. of port per cuft. With that rule I should be around 54sq.in.

2: The port is very narrow, only 2.5" tall. Are there any negative side effects of having the port this narrow in comparison to a standard wider vertical port?

3: Should I redo the design making the port vertical along the side of the box instead of having it horizontal along the bottom?

4: Where would you add bracing.

 

[lilmaniac2 5,000+ posts]

i would make the port about 2-3 inches shorter and pour resin in that back corner making it a curve

 

[Calikid 5,000+ posts]

make the port bigger, or else port noise FTL //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[SHiZNiLTi 10+ year member]

i would make the port about 2-3 inches shorter and pour resin in that back corner making it a curve

That sounds like a good idea, I plan on doing that and using a 6" diameter PVC pipe as a mold that will form the resin in a perfect curve.

Question though, how long does that much resin take to harden? and does anyone know where to find pics of this being done? I remember seeing a build here with a snake port and he poured resin using this PVC pipe as a mold for all 6 port bends.

 

[SQBubble 10+ year member]

No more pics as of now, but the sub should be here this Friday and I will take a bunch of really hi-detail shots then.
Ok so back to critiquing this design....

There's a few issues that I'd like some feedback on.

1: Im at 81sq.in. of port area. Is this too much for my sub in this 4.5 cuft box? I allways thought you should do 12sq.in. of port per cuft. With that rule I should be around 54sq.in.

2: The port is very narrow, only 2.5" tall. Are there any negative side effects of having the port this narrow in comparison to a standard wider vertical port?

3: Should I redo the design making the port vertical along the side of the box instead of having it horizontal along the bottom?

4: Where would you add bracing.

rule of thumb is 16sq.inch each cu.ft, 81sq.inch should be ok, little bit more would be better IMO

 

[btnhfan 5,000+ posts]

APX motor?

 

[tommyk90 5,000+ posts]

Now, IMO.

81 square inches is TOO much port area. For a daily driving enclosure I would do something more like 50-60 square inches of port area.

Also, I don't like those port dimensions either. Having a port that wide, with that little height could cause some serious port turbulence and port noise.

To correct that and get efficient airflow, I would do a port that follows the HEIGHT of the box, rather than the WIDTH (a vertical port as you put it). This would let the port be wider thus reducing port shuffling/port noise and would let you knock down the port area to get sufficient tuning.

 

[Kenny Pollock 10+ year member]

I'm with Tommy on this one //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Also, what happened to the BTL?

 

[SHiZNiLTi 10+ year member]

I'm with Tommy on this one //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Also, what happened to the BTL?

The BTL is still around. It's getting installed in a 07' Avalanche //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[Kenny Pollock 10+ year member]

Nice, your Avalanche?

Not to ***** the thread... but my Blazer is going black dude! House of Kolor Limetime Pearl on the inside, accents on the black outside.

 

[SHiZNiLTi 10+ year member]

Now, IMO.
81 square inches is TOO much port area. For a daily driving enclosure I would do something more like 50-60 square inches of port area.

Also, I don't like those port dimensions either. Having a port that wide, with that little height could cause some serious port turbulence and port noise.

To correct that and get efficient airflow, I would do a port that follows the HEIGHT of the box, rather than the WIDTH (a vertical port as you put it). This would let the port be wider thus reducing port shuffling/port noise and would let you knock down the port area to get sufficient tuning.

Ya, I had to make the port like that or else tuning would be too high, If I made it 3.5" instead of 2.5" I would have been farting at 47hz with 113sq.in. of port FTL since it's daily.

I'm going to redesign the box so that the port isnt along the bottom. I'll make the port vertical and will still use the idea of using resin with a PVC pipe mold to make the perfect curve.

Anyone know how long this much resin would take to cure?

What about (4) PRECISION PORT 4" FLARED PORT's at 18" long? That would get me at 38hz tuning with 50sq.in. of port area. Would that be any better then using resin to make a perfect curve?

Do you guys think I should stay aroudn 4.5 cuft or do 4 cuft?

Keep in mind this is a daily setup.

 

[j3bus2k3 5,000+ posts]

Why not some Aeros? Would take up much less space, and could get away with using alittle less port area. Only problem I would see is the actual length...