box tuning

[Johnny Law.Lulz 5,000+ posts]

I got a week ban for calling out Forceww's worthless contributions, the way nismo's acted and all and then i came here and made a thread so they banned me permanetly. I think itsfunny how the staff there bashes this site there but i cant do the same. But this site generates more sales for me then they did.

 

[wenn_du_weinst 10+ year member]

I usually just lurk on here don't post to often

 

[Johnny Law.Lulz 5,000+ posts]

I see your name all the time but you never post lol.

 

[SicAudio 5,000+ posts]

You're really bad at reading comprehension, aren't you? You just said the sub needs 2ft^3 net, which is after ALL displacements. THAT IS WHAT YOU USE TO FIND YOUR PORT LENGTH, IT'S WHAT YOU PLUG INTO THE CALCS FOR CHRIST'S SAKE.

wow you didnt understand what i meant at all dude lol. nevermind i will do it my way it has always worked great.

 

[RAM_Designs 5,000+ posts]

wow you didnt understand what i meant at all dude lol. nevermind i will do it my way it has always worked great.

No, your logic makes no sense at all. The step by step way that I quoted works fine. For some reason you think that gross volume is important when tuning...it isn't. If you do it your way you have been tuning a good 3-5hz higher than you intended to do. Like I said, how can a calculator figure in how you're building the port? It can't. Your way is wrong and flawed in many ways...I can sit here and tear holes in your argument for as long as you want me to. It's wrong, deal with it, and start doing it right...I certainly hope you don't build boxes and designs for other people. //content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

 

[RAM_Designs 5,000+ posts]

Here, I'll even do a step by step with real world numbers.

-I have a pair of 10" AA Assassins that I want to put in a 4ft^3 box tuned to 30hz.

-I have already determined that I'll be using a 14x48" face with whatever depth I need to get the volume I need.

-I'll use a side firing 8" aeroport to make this easier without having to deal with a slot port with turns in it.

-Plugging the 4ft^3 figure and 30hz tuning into the carstereo.com calc, I get a hair under 32" port length. This is equal to slightly under 1ft^3 port displacement, so let's say port/sub displacement is about 1.25ft^3.

-So now I know that my gross box volume needs to be roughly 5.25ft^3, so I plug my 48x14 figures into carstereo.com's box volume calculator, along with my desired gross volume(5.25ft^3) and wood thickness(.75"), and find out that I need the box to be 17-1/8" deep to have a 5.25ft^3 gross volume, which after port and sub displacement, will give me 4ft^3 tuned to 30hz.

 

[RAM_Designs 5,000+ posts]

Anyways, I'm done arguing with a brick wall. It's been explained as simple as can be a few times now.

 

[mrezstreet 10+ year member]

Ok if sub A needs to have 2.^ft and I want it at 32hz I do mostly slot so I have L and W already fixed fing needed lenth....map it on box if it bends and find lenth of the port wall x .75 for thikns and wall higth...add dis of sub bracing ect end up with 2.75^ now and I know know the deepth of box...its tuned to 32hz on 2^ cuz that's after disp! If you tune before port dis you will ALWAYS be off ( not a lot in some cases) but for spl that why we tune to mic not paper

 

[mrezstreet 10+ year member]

If you are using pipe or areo's truth is that the dis of the ports most of the time won't change tuning enuff to hear it. But slot ports not so much. I have ports 12.5" tall by 25" long. .15-.25^ ft can be a few hz that kills ur subs.

 

[SicAudio 5,000+ posts]

Here, I'll even do a step by step with real world numbers.
-I have a pair of 10" AA Assassins that I want to put in a 4ft^3 box tuned to 30hz.

-I have already determined that I'll be using a 14x48" face with whatever depth I need to get the volume I need.

-I'll use a side firing 8" aeroport to make this easier without having to deal with a slot port with turns in it.

-Plugging the 4ft^3 figure and 30hz tuning into the carstereo.com calc, I get a hair under 32" port length. This is equal to slightly under 1ft^3 port displacement, so let's say port/sub displacement is about 1.25ft^3.

-So now I know that my gross box volume needs to be roughly 5.25ft^3, so I plug my 48x14 figures into carstereo.com's box volume calculator, along with my desired gross volume(5.25ft^3) and wood thickness(.75"), and find out that I need the box to be 17-1/8" deep to have a 5.25ft^3 gross volume, which after port and sub displacement, will give me 4ft^3 tuned to 30hz.

no that i do understand which is all i was asking for thank you finally lolz

i just wanted a simple explanation how you do it that was all.

 

[RAM_Designs 5,000+ posts]

no that i do understand which is all i was asking for thank you finally lolzi just wanted a simple explanation how you do it that was all.

All I did was use real world numbers; it's still the same process that you said didn't make sense, for some reason.

1) Figure out what net volume you want

2) Figure out the port size and length needed to tune it to what you want

3) Figure out the port displacement

4) Add 1&3 together

5) Design a box that has that much gross airspace"

 

[SicAudio 5,000+ posts]

i just wanted it laid out i couldnt wrap my head around making the box that way i have always figured what my max space i could use was then adjusted the tuning to that while trying to keep enough vb for the sub, make box smaller ect whatever it took.

 

[RAM_Designs 5,000+ posts]

i just wanted it laid out i couldnt wrap my head around making the box that way i have always figured what my max space i could use was then adjusted the tuning to that while trying to keep enough vb for the sub, make box smaller ect whatever it took.

But you said that you don't take port displacement into account when finding the port length.

 

[mrezstreet 10+ year member]

All I did was use real world numbers; it's still the same process that you said didn't make sense, for some reason.
1) Figure out what net volume you want

2) Figure out the port size and length needed to tune it to what you want

3) Figure out the port displacement

4) Add 1&3 together

5) Design a box that has that much gross airspace"

Sic...if you are going for max...then working off that...you can get close...but if you want it on the money^^^^ then *sing* this is how we do it....

 

[SicAudio 5,000+ posts]

yeah i knbow i just wanted to know both ways is all. the whole thing got blown way out of proportion. 3.75 minus all displacement ( including port!! ) came to 3.16 12.5x3" x 16.25 is 37.5 hz thats what my math said and 3.16 is a ton better vb for a 12" rd alpha than a meesly 2.6 was gonna be so...................

i get flamed for that lolz