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walkychalky
08-11-2005, 04:01 AM
Currently I have two 12's but am upgrading to two 15" RE SX's.....they will be powered by an orion 2500d.... here is a quick sketch of the box i am using now: http://img357.imageshack.us/img357/9914/enclosure7zy.jpg
It's made with 3/4" MDF

so my question is do u think that this box will be a nice match for my new subs if i cut the holes larger so that they fit 15's? or would u suggest a whole new box?....i would like to keep this one because it fits perfectly in my Grand Cherokee and looks very nice....but i dont want my new subs to sound like **** in it....so any suggestions?....i dont know anthing about building boxes so i would have to pay for someone to build a new one.....so lemme know what your guys opinions are. Also, if anyone could let me know what the box is tuned to n its volume that'd be very helpful....i forgot what it was n dont know how to figure it out. (The calculators only confuse me)

Thanx

kuijo
08-11-2005, 04:14 AM
Looks good, RE recommends 3.5 per 15 SX for SQL, and you're giving them a little under 7.8( i dunno what ur subs displacement is, closer to 7 after displacement) for both with a tuning at about 31. pre-displacement of subs.

walkychalky
08-11-2005, 04:57 PM
thanx for ur help....how do i found out the displacement of my subs and how much will the displacement affect tuning??

tRiGgEr
08-11-2005, 05:02 PM
Looks good, RE recommends 3.5 per 15 SX for SQL, and you're giving them a little under 7.8( i dunno what ur subs displacement is, closer to 7 after displacement) for both with a tuning at about 31. pre-displacement of subs.

Wrong.

walkychalky
08-11-2005, 05:04 PM
Wrong.

then what is it really?

kuijo
08-11-2005, 05:06 PM
Wrong.

very informative

:handclap:


Its either 7.8 @31 or 6.3@34 depending on how u measured it.

tRiGgEr
08-11-2005, 05:07 PM
Box = 6.73 before any displacments. Granted those are external dimmensions.
Port displacment = 0.56
Speaker displacment will be 0.36

So 5.81ft^3 after displacment. That's only 2.91ft^3 each and you will need a bigger box...

tRiGgEr
08-11-2005, 05:09 PM
Oh and your current box is tuned to 34.5hz...

walkychalky
08-11-2005, 05:17 PM
was it wrong because he used those as if they were internal mesurements??

kuijo
08-11-2005, 05:20 PM
Ya.

walkychalky
08-11-2005, 05:30 PM
so if i wanted 3.5 cubes per sub after port and sub displacement.....tuned to about 32 Hz...... what would the LxWxH (external) have to be?....would it fit in a space thats 45x21x19?.....

kuijo
08-11-2005, 05:32 PM
Youd be a little shy with those exact dimensoins after sub displacement.

tRiGgEr
08-11-2005, 05:34 PM
Yes. But you may not get the disired port area for 2 15's.

walkychalky
08-11-2005, 05:35 PM
could u give me the dimensions it would take.....maybe extending the length and width a lil bit....i could maybe gain an inch or two either way....or would this still not be enough?

tRiGgEr
08-11-2005, 05:47 PM
Actually those dimmensions wrok out pretty good.

Box - 45" x 21" x 19" = 8.59
Slot Port - 17.5" x 4" x 16" = tunned to 32hz(31.83)

Each speaker will have 3.73ft^3

walkychalky
08-11-2005, 05:56 PM
Actually those dimmensions wrok out pretty good.

Box - 45" x 21" x 19" = 8.59
Slot Port - 17.5" x 4" x 16" = tunned to 32hz(31.83)

Each speaker will have 3.73ft^3

that sounds great.....will the extra .23 cubes per sub make much of a difference in performance?

tRiGgEr
08-11-2005, 05:58 PM
that sounds great.....will the extra .23 cubes per sub make much of a difference in performance?

Yep. You can shave about an inch If you wish to get back down to 3.5 each. But I find with a bigger box the Low end is much louder:yumyum:

kuijo
08-11-2005, 05:58 PM
He didn't take in account sub displacement so it'll be a little shy.

walkychalky
08-11-2005, 06:03 PM
well he said b4 that my sub displacemnt would be .36....so that would make it .18 per sub....meaning that each sub would have 3.55 cubes?...is this right??

tRiGgEr
08-11-2005, 06:05 PM
He didn't take in account sub displacement so it'll be a little shy.

If you are refering to me, yes I did.

Total box volume 8.59
Total port displacment 0.77
Sub Displacment .36

Volume after displacment - 7.46

3.73 each sub...

:p:

kuijo
08-11-2005, 06:06 PM
Go build the box.

kuijo
08-11-2005, 06:07 PM
If you are refering to me, yes I did.

Total box volume 8.59
Total port displacment 0.77
Sub Displacment .36

Volume after displacment - 7.46

3.73 each sub...

:p:


weird, my program says theres more port displacement then that.

walkychalky
08-11-2005, 06:07 PM
Go build the box.

are u saying that to say he will see he's wrong when its built or are u telling me since i now have the dimesnsions i should go build it??

tRiGgEr
08-11-2005, 06:09 PM
weird, my program says theres more port displacement then that.

17.5 x 4(.75 wood wall used as part of the port for a slot port) x 16 = 1330 / 1728 = 0.77 ft^3...

walkychalky
08-11-2005, 06:13 PM
thanx for all ur guys' help...i think im going to use the dimensions u gave me trigger...u seem pretty confident with them and are able to back them up....i'm going to be mounting a couple amps on the box as well....will i need to use a thicker wood than 3/4" mdf or just use some screws that are only about 1/2"?

tRiGgEr
08-11-2005, 06:17 PM
thanx for all ur guys' help...i think im going to use the dimensions u gave me trigger...u seem pretty confident with them and are able to back them up....i'm going to be mounting a couple amps on the box as well....will i need to use a thicker wood than 3/4" mdf or just use some screws that are only about 1/2"?

You would be best using a double baffle and adding some bracing. It will decrease your internal volume but you have an extra .23ft^3 each speaker to work with. And it wont effect your tunning drastically.

1/2" screws will be fine. Just make sure the equipment being screwed is secure.

And remember 2 15" SX's are going to have a lot of output. Bracing, bracing, bracing:D

walkychalky
08-11-2005, 06:22 PM
You would be best using a double baffle and adding some bracing. It will decrease your internal volume but you have an extra .23ft^3 each speaker to work with. And it wont effect your tunning drastically.

1/2" screws will be fine. Just make sure the equipment being screwed is secure.

And remember 2 15" SX's are going to have a lot of output. Bracing, bracing, bracing:D

to be honest i have no idea what anything u said just means.....i'm not planning on building the box myself....i just want the info to pass on to the builder....now the only problem is finding someone who will build it for me for a reasonable price...i think i'll try the forum first to find someone near me....if not i might have someone make plans and give them to a local carpenter or something....what would u say would be a reasonable price for this box?....i dont want to get myself ripped off

kuijo
08-11-2005, 06:25 PM
are u saying that to say he will see he's wrong when its built or are u telling me since i now have the dimesnsions i should go build it??


no i'm saying you should go build the box and get some real expierence.

tRiGgEr
08-11-2005, 06:27 PM
Double baffle - 2 peices of wood glued together to make a 1.5" board to screw the subs on to. It is much stronger.

Bracing - Wood used inside the box to keep the box from flexing. Makes a more stable enclosure.

Bracing inside the box takes up space so it will make your box smaller. But as mentioned do not worry to much about it.

Just so you know:D

And for that large of a box at a shop around $150-$200.

I would seriously take a crack at building it yourself. Save you a butt load of money.

walkychalky
08-12-2005, 06:24 AM
so my new box should look like this??

http://img362.imageshack.us/img362/492/enclosure5ki.jpg

and if you could....will u maybe add some bracing to that picture to give me an idea of where it should go?

walkychalky
08-12-2005, 11:33 PM
bump....calling trigger...calling trigger.....