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PokeFan
06-23-2008, 12:45 PM
Can someone help me out with this? I need to know what the ports should be for this box.

This is what I've come up with I think it's right.
Wedge box
2 8" L7's
42x16
top depth=3.5 bottom=9
Tuned to 30hz

Box should be 1.53^3 @30hz

I don't know what other info you need if any let me know.

Jeremy M
06-23-2008, 12:51 PM
.....well i dont' think this is accurate but i'm showing the port to be 1" wide and about 24.5" long........4.5 deep, and 20" long.....being that the port will be L shaped

NissanKicker
06-23-2008, 12:57 PM
.....well i dont' think this is accurate but i'm showing the port to be 1" wide and about 24.5" long........4.5 deep, and 20" long.....being that the port will be L shaped

You're correct...
.... Crazy box... but you're correct.

PokeFan
06-23-2008, 01:03 PM
lol, So Nissan. Are you saying this is a bad design or just weird?

Jeremy thanks, but you kinda lost me here. So if the ports are to be 24.5" long my only option would be the front face of the box facing the rear right? So the opening would be 1" tall and 24.5 long across the bottom?

The 4.5 deep and 20 long is where you lost me though. Is that 4.5 back and then 20 up? If that's the case would the back being at a slant affect that port size?

PokeFan
06-23-2008, 01:05 PM
Sorry simple math could've figured that I guess. The total port should be 24.5" with a 1" opening right? So do the opening dimensions matter as long as it's 1" opening?

NissanKicker
06-23-2008, 01:14 PM
Well... It's a truck box.
Question:
... Why are you wanting it tuned to 30?
I'd do 40hz at the lowest.

The total port length is 24.5 ( 4.5" back & 20" to the right - port opening will be on the left front side ).

... for this is work... It has to be a 1" opening.

Jeremy M
06-23-2008, 01:16 PM
yah it's a 1" wide opening, then it goes back 4.5 inches, then makes a 90 degree turn and goes for 20"

that will give u ur tuning.....

Jeremy M
06-23-2008, 01:16 PM
that's with port forward BTW.

PokeFan
06-23-2008, 01:24 PM
Yes, it's essentially a truck box. I'm trying to get away with taking up as little room as possible in my rear cargo area. With those top and bottom dimensions it will sit flush with the top of my seats and basically just go straight down.

I don't know anything about the tuning. I found a calculator online that you put in all the sub info and it kicked out the tuning specs. I'm up for suggestions and if I need to look at this again I'm all for it. Any help at this point is appreciated.

Jeremy M
06-23-2008, 01:27 PM
i think and this is my opinion, that 30hz on those 8's is really low but i could be wrong. Unless u have good mid's to pick up some of the bass.

PokeFan
06-23-2008, 01:29 PM
Mids are decent but I wouldn't count on them picking up enough of the bass to make me happy.

NissanKicker
06-23-2008, 02:33 PM
Soo.. I'd do more like 40hz - 50hz tuning range
Probox ported truck enclosures are 50hz... And they are IMPRESSIVE! so, 50hz MAX - 40hz MIN

PokeFan
06-23-2008, 02:40 PM
Well, I played around a bit and came up with a 40hz before I saw your post. Should I shoot for 50 instead? 45?

Here's what I've got but the only issue is this box will be facing the other direction. How would I go about making the port against the slant? Subs will be mounted to the flat face and the angle will be against the seat. Does this create other problems?

http://i34.photobucket.com/albums/d105/gwpowers/box.jpg

dman4486
06-23-2008, 02:50 PM
tuning will depend on what you want to achieve from the sub stage....30 for 8's is low, but not unheard of! if you want outstanding range and sq, then 30hz with the correct 8 can sound very good.

I have 2 10s tune at 24hz and they sound amazing on the lows with extremely flat response which was my target.

NissanKicker
06-23-2008, 02:53 PM
You might be better off using a Sqaure port...
... 40hz is good... 45hz is good... 50hz is good.
( just depends on what you're shooting for:

40hz * universal * ( good lows, GREAT MIDS, good highs )
45hz ( Decend amount of lows, GREATER MIDS, Great highs )
50hz ( Limited Lows, GREATER MIDS, Greater highs )

- 30hz ( GREAT lows, good mids, limited highs )

PokeFan
06-23-2008, 02:53 PM
That's what I'm looking for, a little extra punch out of the subs but with SQ in mind. I still want a really nice flat and crisp sound just want that little extra push as well.

PokeFan
06-23-2008, 02:56 PM
You might be better off using a Sqaure port...
... 40hz is good... 45hz is good... 50hz is good.
( just depends on what you're shooting for:

40hz * universal * ( good lows, GREAT MIDS, good highs )
45hz ( Decend amount of lows, GREATER MIDS, Great highs )
50hz ( Limited Lows, GREATER MIDS, Greater highs )

- 30hz ( GREAT lows, good mids, limited highs )

Hmm, Maybe I do want to go back down to the low 30's then. The higher bass would be just fine with my comps maybe decent in the mid bass but I'm not counting on them for that. I definitely want the good lows though. I like the bottom notes more than anything. Think of that first little beat in Twista - Front porch. A little old but **** I still love that song.

NissanKicker
06-23-2008, 02:58 PM
Yeah... it's like a 15hz - 20hz note...
... Well, go back to 30hz use a sqaure port. I'm about to figure out something.

dman4486
06-23-2008, 03:02 PM
If I was building this enclosure I would tune in the mid to upper 30's. I love the lows, but "lows" can be a range depending on the person.

Mainstream music doesn't typically extend below the upper 30's, so if you plan to stick with the the mainstream, then the upper 30's or lower 40's(as Nissan said) would be perfectly fine for you

I like songs like "White girl" by jeezy (29hz) for showing off the 10s:D

dman4486
06-23-2008, 03:07 PM
Yeah... it's like a 15hz - 20hz note...
... Well, go back to 30hz use a sqaure port. I'm about to figure out something.

and no..if it is the song I am thinking, it is not that low

I don't have my spectrum analyzer on this computer, but i think it is mid 30's minimum

edit: http://www.youtube.com/watch?v=_L8kgHK8qOQ ..............that low is 29hz

NissanKicker
06-23-2008, 03:09 PM
I thought that note was lower than that...
... but the last time I played that song was when I was using my 4 12cvxs. So that would make it seem lower.

the727kid
06-23-2008, 03:15 PM
Tuning the subs lower doesn't just let the subs play lower, it also gives them a deeper sound, and makes more **** flex =D. IMO low tuning FTW.

NissanKicker
06-23-2008, 03:42 PM
http://i214.photobucket.com/albums/cc75/NissanKicker/28portedtb.jpg

BEAVER.989
06-23-2008, 03:47 PM
You'll want to vent out the side so that you're not choking the port. I'd do a simple round tube port, for simplicity's sake.

NissanKicker
06-23-2008, 03:49 PM
You'll want to vent out the side so that you're not choking the port. I'd do a simple round tube port, for simplicity's sake.

Now that I look at it
... Circle port would be an easier build.

dman4486
06-23-2008, 03:51 PM
Now that I look at it
... Circle port would be an easier build.

how old are you? just curious because you are very indecisive and impulsive

NissanKicker
06-23-2008, 03:53 PM
I'm 21.
... I just have alot of ideas in my head. For me to be satisfied w/ anything. I have to put everyone option out, build it, test it and compare.

dman4486
06-23-2008, 03:55 PM
I'm 21.
... I just have alot of ideas in my head. For me to be satisfied w/ anything. I have to put everyone option out, build it, test it and compare.

interesting approach

NissanKicker
06-23-2008, 04:07 PM
lol...
.. But back on topic!
Question: Is that something that you've had in mind ( enclosure picture )

PokeFan
06-23-2008, 04:28 PM
Sorry, I went to lunch and missed a few post. For the most part that's what I'm looking for but it's a pretty tight squeeze to get the box in and the port would be right up against the side wall. I think I'm going to have to have it come out the front. I was thinking round ports as well for simplicity sake.

NissanKicker
06-23-2008, 04:32 PM
Since you're wanting the subs on the flat piece. ( Not on the slant )
... You are limited to choice... I'll put a model of the circle port.

NissanKicker
06-23-2008, 05:09 PM
Here goes the model...
http://i214.photobucket.com/albums/cc75/NissanKicker/28portedtb2_FullScreen.jpg

BEAVER.989
06-23-2008, 05:17 PM
Either these subs are a lot shallower than I think they are... or that model is not going to work very well.

PokeFan
06-23-2008, 05:19 PM
I don't think the port would work side firing would it? It will be right up against a wall. And what size is that port? Looks to be around 7" is that big or not?

Beaver, I'm glad you brought that up. I almost forgot the subs need to be mounted on the bottom half of the box. they have a 4.75 mounting depth so they have to be under that part of the slant.

NissanKicker
06-23-2008, 05:21 PM
lol... I shrunk the measures by 1/2 to get the entire enclosure... the top depth is only 1.75" on the model... It's actually 4.5 top.

dman4486
06-23-2008, 05:23 PM
I don't think the port would work side firing would it? It will be right up against a wall. And what size is that port? Looks to be around 7" is that big or not?

Beaver, I'm glad you brought that up. I almost forgot the subs need to be mounted on the bottom half of the box. they have a 4.75 mounting depth so they have to be under that part of the slant.

with your layout, side fire port will not work, as you will have no space for the port to breath

PokeFan
06-23-2008, 05:25 PM
Am I trying to build a pain in the a$$ box or am I just not understanding this very well?

NissanKicker
06-23-2008, 05:38 PM
a pain in the A$$ box... You need more room.
... Try:

42"w x 16"H
Top Depth = 6"
Bottom Depth = 12"

BEAVER.989
06-23-2008, 05:41 PM
Also, if 42" is your maximum width available, the box should be made 38" wide to allow for the port to breathe.

PokeFan
06-23-2008, 05:51 PM
ok, how about this?

38x20 3.5top 10bottom

According to THIS (http://www.the12volt.com/caraudio/boxcalcs.asp#por) a 2" diameter port would only need to be 2.16" to tune to 36hz in a 1.8^3 box. Does that sound right?

BEAVER.989
06-23-2008, 05:57 PM
a single two inch port is gonna whistle like crazy. plan on stepping up to a 4" port, or dual 2"ers.

Also, the measurements you just listed make the enclosure 1.6cft. GROSS. once you account for driver and port displacement you're looking at much less... which will require longer ports.

If you can supply me all of the ts parameters I'll see if I can model something up for you.

NissanKicker
06-23-2008, 06:07 PM
http://i214.photobucket.com/albums/cc75/NissanKicker/28portedtb3_FullScreen.jpg

38"W x 16"H
Top: 6"
Bot: 12"
Port: 5" x 5" x 25.5"
Tuning: 30hz

PokeFan
06-23-2008, 06:10 PM
Here you go...
http://i34.photobucket.com/albums/d105/gwpowers/L7-1.jpg

I'd really like to keep the top and bottom at 3.5 and 9.5-10 if at all possible. The height can up to 20" if need be

NissanKicker
06-23-2008, 06:16 PM
Like you stated... Pain in the A$$ enclosure.
... Someone else with alittle more experience give it a shot.

educatedink
06-23-2008, 06:17 PM
I know all too well about pain in the *** enclosures. GL with this one.

PokeFan
06-23-2008, 06:26 PM
lol, thanks guys. I really do appreciate the effort you put in Nissan. Thanks bud

BEAVER.989
06-23-2008, 06:30 PM
38x16x3.5t/10b

Add a 4" port that is 15.75" long and you'll end up with 1.373cft. NET after port and sub displacement with a 36hz tune.

It actually looks really good on the graph... models pretty flat and should have pretty decent sound quality. Be sure to use a SSF set to somewhere in the neighborhood of 30hz to prevent over excursion on the low lows.

Happy building. :D

PokeFan
06-23-2008, 06:40 PM
Beaver thanks I appreciate it. 1.373 is pushing the minimum enclosure is there any way at all to push that to 1.5? Or do you think yours would be fine?

Oh, and what is SSF? sorry....

BEAVER.989
06-23-2008, 06:41 PM
I think it's fine, but if you really want to go taller I'll rework it.

NissanKicker
06-23-2008, 06:45 PM
HAHAHA!... I know right!

BEAVER.989
06-23-2008, 06:47 PM
Increase the height to 17.5" and reduce the port to 14" and you'll have 1.6cft. NET @ 35hz... this looks even better, if it'll fit.

SSF=Sub Sonic Filter

PokeFan
06-24-2008, 09:31 AM
Thanks Beaver I appreciate it! It will fit it's the cargo area of a Jeep, no problems there. Quick question, Does the placement of the subs to the port chamber matter? Could I have the subs on either side of the box and the port coming out one side or if the sub is on the right should the subs be on the right as well?

BEAVER.989
06-24-2008, 11:45 AM
I would stuff the subs all the way to one side of the enclosure and fire the port out the opposite side. If they're going to be rear firing I'd probably hug the drivers side with the subs and vent out the passengers side, FWIW.

PokeFan
06-24-2008, 01:33 PM
Alright, So how does this look?

http://i34.photobucket.com/albums/d105/gwpowers/subBox.jpg

BEAVER.989
06-24-2008, 01:58 PM
I don't think the box is deep enough at the top to allow you to mount the sub that high. I'd put 'em low in the box, myself... otherwise, nice.

PokeFan
06-24-2008, 02:16 PM
I keep forgetting that. *Updated*

Where can I find a SSF? Everything I've been able to come up with is integrated into an amp already.

I also found this,
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=268-352

Anyone ever used these or have any suggestions for something else?

BEAVER.989
06-24-2008, 02:22 PM
To the best of my knowledge the only way you'll get a ssf is to buy an amp with that feature... I could be wrong, though.

Otherwise, depending on the rest of your set-up, you could set the x-over on the head unit at 30/24db HP and then use the amps x-over for LP duty... Like I said, it depends on the capabilities of the rest of your gear.

Depending on the type of music you listen to, you may not even need a ssf...

PokeFan
06-24-2008, 04:41 PM
Ok, at the risk of sounding stupid. How would I cut the angles on the top and bottom pieces?

Perfectionist
06-25-2008, 03:25 AM
hey pokefan have you come right with your enclosure details? me personally i would have done a few things different but in this game its all about what you want. to cut the angles you must use a table saw, a circular saw or a jig saw. otherwise you can ask the guys you buy the timber from to cut it to size for you with the angles. hope that answers your question

PokeFan
06-25-2008, 10:09 AM
Yea, it's pretty much set. This one was basically tuned by beaver but I'm always up for suggestions.

I've got access to a table saw but couldn't figure out how to cut those angles with it. I mean the one that runs the length of the boards on the top and bottom not the long angles of the side pieces.

Perfectionist
06-26-2008, 02:26 AM
the quickest way to cut the angle is to use a bevel square. get your angle i think yours was around 70 degrees. using a protractor line up the 0 and 180 degree line with the edge of a piece of timber and mark your angle. take the bevel square press it up against the edge of the timber and line up the 90 degree mark with the center of the bevel square and the angle you marked with the moving part of the bevel square. tighten butterfly nut and you have your angle. place the bevel square on the table saw and move the blade to the angle you have on the bevel square. otherwise you can use a piece of scrap timber. mark as i said previously. draw a line between the 90 degree mark on the bottom edge of the timber and the angle you have marked. cut along this line with a jig saw and you have your angle