Help me build a box for my 2 10" SWRs

[tommymilan311]

Okay, so I've been playing around with WinISD and need to know if I'm heading down the right path, some tips and tricks, the works.

What I did was grab the specs of my current box to compare. It currently a "prefab" and you can find it here: My Lil Prefab

I believe I'm at 800ish watts for the two. Amp isn't what I thought, I was taking advise from someone who I now realize just knows how to hook things up and break them. He really has no idea what clean power is or sounds like, so I've been left with a 300$ piece of useless equipment (Not really, its a nice amp, 1100 at 2 ohms, just is no good for 1 ohm). I am on the prowl for a deal and will pounce when I see it. No set budget, looking right now, but I am happy with the 800W so far.

I've done some different charts. One with my box at 800W, one with my box at 2000W, what I thought looked like the optimum combination of size and port for 800W, another for 2000W which ended up close to the same as the 800W. Here are the charts, let me know if any other will be helpful:

Yellow = Current box at 800W, 2.5FT^3, 35Hz, Port(2) - 10.5 X 1.25 X 20.25

Light Yellow = Current box at 2Kw, 2.5FT^3, 35Hz, Port(2) - 10.5 X 1.25 X 20.25

Red = Optimum box at 800W, 4.0 FT^3, 32Hz, Port(2) - 12 X 3 X 42.22

Cyan = Optimum box at 2Kw, 4.0 FT^3, 32Hz, Port(2) - 12 X 3 X 42.22

Transfer Function Magnitude:

https://www.dropbox.com/s/4b81dbfgwgqhb7v/Trasfer%20Function%20Magnitude.png?dl=0

SPL:

https://www.dropbox.com/s/n80gdj0ahb56lhh/SPL.png?dl=0

Air Port Velocity:

https://www.dropbox.com/s/5d7mw62iw6d13y5/Port%20Air%20Volocity.png?dl=0

This to me seems like the big one. Isn't this the "boomy" sound? So revealing that would be great as it has become very evident.

Sorry for all the Enclosure design posts lately. I'm just trying to understand why we do what we do, and how it all works.

Thanks for all and any help.

Click to read more...

 

[big scott]

no pics.

 

[tommymilan311]

no pics.

Pics of the subs?

 

[ThatChevyGuy 5,000+ posts]

i really hope you didnt pay $100 for that shit box...

 

[tommymilan311]

i really hope you didnt pay $100 for that shit box...

PSST no, I would have bought one here. It was like $60 when I bought it. What is so bad about it? That is what I'm not understanding, SPL is about the same, the big difference comes from air velocity.

 

[ThatChevyGuy 5,000+ posts]

PSST no, I would have bought one here. It was like $60 when I bought it. What is so bad about it? That is what I'm not understanding, SPL is about the same, the big difference comes from air velocity.

air volume, port area, shoddy construction, etc.

also, none of your pics are working.

 

[tommymilan311]

air volume, port area, shoddy construction, etc.

see, but why? I've been told this, but then the numbers don't show a huge difference. What I get is that the port area being bigger requires more port length, which brings down the port air velocity, which is the "boomy" sound I believe. I understand that and why we do that.

But why is air volume a big deal when nothing on the charts is evident of that? What it sounded like, to me, was that with a bigger air volume you'd get more SPL, but that was not the case when using WinISD, only a slight increase. This is the part I'm not understanding. Also, my sub specs are asking for a 1.3FT^3 at the high end.

As for the construction. I think that is unfair to say as you haven't personally seen the box. This was a much better construction than I think I could do personally. And they sealed and double sealed the inside of the box, which was evident. It seemed like a solid construction.

Sorry for being a pain, I'm just no good at accepting information without a reason as to why. I'm one of those guys who must know why we do what we do, I don't just accept that we do what we do. Ya know?

 

[tommymilan311]

also, none of your pics are working.

There not? Ugh, they work on my computer. let me dig in and find out why....

 

[ThatChevyGuy 5,000+ posts]

see, but why? I've been told this, but then the numbers don't show a huge difference. What I get is that the port area being bigger requires more port length, which brings down the port air velocity, which is the "boomy" sound I believe. I understand that and why we do that.
But why is air volume a big deal when nothing on the charts is evident of that? What it sounded like, to me, was that with a bigger air volume you'd get more SPL, but that was not the case when using WinISD, only a slight increase. This is the part I'm not understanding. Also, my sub specs are asking for a 1.3FT^3 at the high end.

As for the construction. I think that is unfair to say as you haven't personally seen the box. This was a much better construction than I think I could do personally. And they sealed and double sealed the inside of the box, which was evident. It seemed like a solid construction.

Sorry for being a pain, I'm just no good at accepting information without a reason as to why. I'm one of those guys who must know why we do what we do, I don't just accept that we do what we do. Ya know?

Ill let someone give you a more educated reply...

 

[tommymilan311]

air volume, port area, shoddy construction, etc.
also, none of your pics are working.

You wanna do me a quick favor and check the links to make sure they work?

 

[tommymilan311]

no pics.

Sorry about that, for whatever reason the pics show up on my computer :/ I did post the links to the pics under where the pics are supposed to be. Let me know if you have any trouble.

 

[tommymilan311]

Ill let someone give you a more educated reply...

Thanks. I've been trying to get some of this answered for a while. Its frustrating because IDK how to google. I go down the wrong roads that often contradict that information. Just trying to be as educated as possible, and when I recommend somebody to a bigger box, or a bigger port, or whatever it may be, I want to be able to tell them why they should do that, what it does to make it louder or sound better.

I'm an engineer, accepting information isn't easy for me. I don't usually share this info, but its like asking me to believe in god. There is nothing to show that god is there, you just want me to take your word for it. I can't do that, ya dig?