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View Full Version : First build, 2Cu Ft.@ 27 Hz



DDSC
07-07-2007, 04:29 AM
Is that going to give me strong lows AND tight response

spoonraker
07-07-2007, 05:16 AM
Assuming it's for a single sub, probably a 12'' I'm guessing? Yes, should get nice and low, sound good, but have decent output.

phyphoestilic
07-07-2007, 05:20 AM
Tuning below 28hz in a car audio application is just overkill. I'd say 28-30hz is fine if ur looking for some low end output.

spoonraker
07-07-2007, 05:33 AM
He wants to communicate with elephants obviously

mazdakid
07-07-2007, 07:36 AM
thats pretty low for a 12, what kind of sub is it?

helotaxi
07-07-2007, 10:48 AM
It all depends on the sub. Tuning some subs that low will create a shelf in the low end response and cost total output and usually have pretty nasty group delay as well. Tuning other to that freq is actually higher than the sub wants leading to a large hump in the response that is exaggerated by the car's transfer function. The result is that the low bass is pretty overbearing.

DDSC
07-08-2007, 04:58 PM
Its a Audiobahn Immortal, I finished the ox last night or shall I say this morning (ran into some problems). If I put glue in the joints of the box (the corners) should I still use silicone or will it be fine like that. also how long do you guys let your boxes sit to dry before you hookem up. The glue bottle said wait 24 hrs befor putting stress on the joints but I've got screws every 2"

jellyfish420
07-08-2007, 05:19 PM
screws every 2" is not only overkill...but its actually bad for the box. the only purpose of the screws is to hold it untill the glue dries. i usually do every 5-6". to prove a point i've built boxes, then after the glue dries, remove every screw. the glued joint is actually stronger than the rest of the wood. i usually hook em up as soon as i'm done ;)
i guess you missed my last post in your other thread. i recommended 33hz.

DDSC
07-08-2007, 05:26 PM
I was thinking about that well, at least it LOOKS like fort knox=). Ill remeber that for the next box, which should be next week for 2 12's

Fattony911
07-08-2007, 05:46 PM
screws every 2" is not only overkill...but its actually bad for the box. the only purpose of the screws is to hold it untill the glue dries. i usually do every 5-6". to prove a point i've built boxes, then after the glue dries, remove every screw. the glued joint is actually stronger than the rest of the wood. i usually hook em up as soon as i'm done ;)
i guess you missed my last post in your other thread. i recommended 33hz.

x a gajillion, i also make most of my boxes screwless now because of this, not to mention it looks **** like one peice of wood

PV Audio
07-08-2007, 11:10 PM
Everything in this thread here is pretty much true. You don't need to tune that low in an automotive environment for two reasons: first, there isn't that much low information in music, and more importantly, a phenomenon called cabin gain allows your vehicle to "boost" the output of the bass notes already. Also, 4" or more spacing is fine on screws. Hell, on home audio speakers, I space every 8"...if at all.

DDSC
07-09-2007, 01:54 AM
well I ended up doing 2.5 Cu Ft. at 28 hz just got the thing hooked up and took it around the block **** I can feel the lows in my throat like crazy. I lost a little on the upper end but thats ok cause the Immortal hits the highs harder anyway but ****, I set off my first car alarm with that sub, or any single sub for that matter. I dont think I'll every buy a prefab box again. Now Im wondering what size I should I should make the box for the 2 12's I got on the way, as you will see that one box at 2.5 cubes its taking all the space in the trunk up. If I make one the same size and tuning will it sound the same just louder???

Anyway enough of that, on to the pics.

DDSC
07-09-2007, 02:18 AM
Results of my trip to the store, that circular saw was only 37 dollars at lowes or home depot:yumyum:
http://a448.ac-images.myspacecdn.com/images01/89/l_c36e343af367cfc313c5c8bde64bbf37.jpg
The old prefab box......:zzzzz:
http://a102.ac-images.myspacecdn.com/images01/115/l_f05133d46a69241c8da5844fe5ddc96d.jpg
Side by side along with my new 8 gauge speaker wire
http://a272.ac-images.myspacecdn.com/images01/80/l_0747384ba6db84fa484e2c540285cd47.jpg
I got King Kong in da trunk!!!!!
http://a650.ac-images.myspacecdn.com/images01/90/l_5652d20d80fa5ec0ac754baa46e97ed1.jpg
2 24" clamp ghetto rigged to make one big one, those are 4 dollars each at harbour freight.
http://a910.ac-images.myspacecdn.com/images01/71/l_b8b7737a8c9568cb773403dd63f16db5.jpg
http://a717.ac-images.myspacecdn.com/images01/65/l_147b08366078f4b088ba862e01367f2c.jpg
Gotta make sure everything fits up right before I start screwin
http://a123.ac-images.myspacecdn.com/images01/83/l_6938168f684d375e43dad21aed5bdcda.jpg
You cant tell from here but the end of the port wall got sanded to round the edges off a bit, I did it to the mouth of the port too but thats only in the pic when its in the car
http://a718.ac-images.myspacecdn.com/images01/86/l_116f61d08dc91edbbc4e7d33e659702d.jpg

CrazedCat
07-09-2007, 06:48 AM
8 ga. for speaker wire...now THAT'S excessive

jellyfish420
07-09-2007, 07:47 AM
what did i tell you? looking at the original box, you'd be lucky if that thing is 1 ft.
that looks like an 8ga amp kit, not speaker wire. going by your max dim. 37-18-16, i'd try this for you 2 12's...3ft at 35hz
http://img23.imageshack.us/my.php?image=3cubes35hz465sqin4wj.png

DDSC
07-09-2007, 12:01 PM
8 ga. for speaker wire...now THAT'S excessive

:naughty: but I got 40 feet of the 8 for 30 when I would have paid 24 for 16-20 ft of 12, not to mention when the cars off my voltage is reading at 12.2 instead of 12 now and I can listen to the radio alot longer now before the voltage drops.

na_rsx
07-10-2007, 11:43 AM
in for videos

theothermike
07-11-2007, 12:23 AM
wait so ur doubling up 8 ga power wire for ur speaker cable to the box...... wow now that is almost as overkill as robin, iamamp3pimp, triple baffling the green stained box =]. JK Robin.

But, so far looks good. ill be needing some box supplies in a year or so when i decide to do my own.

Mike-

DDSC
07-11-2007, 03:27 AM
in for videos

I made one but its real crappy and my car is hella dusty, Ill try to get my car all cleaned up and make one but Im broke now and dont get paid till thursday, and Im not off till saturday:crying: :greedy: :naughty:

DDSC
07-11-2007, 03:32 AM
wait so ur doubling up 8 ga power wire for ur speaker cable to the box...... wow now that is almost as overkill as robin, iamamp3pimp, triple baffling the green stained box =]. JK Robin.

But, so far looks good. ill be needing some box supplies in a year or so when i decide to do my own.

Mike-

Im not doubling it up, my powers 4 gauge then the speaker wires 8, and why is it overkill its not hurting anything

theothermike
07-12-2007, 10:55 AM
overkill, as in more than what is needed. not the overkill meaning it so much it'll hurt it.

DDSC
07-13-2007, 06:20 AM
Well just got my new Audiobahns in the mail today:cool: , ******* fedex guy actually left the subs sitting on the front porch after nobody answered the door even though I left a note taped to the door saying to put them on the back porch:verymad: , on top of that this is WHILE my girls mom was pulling into the driveway, she could have been anybody and ran off with my sht. but anyway, got them outta the box when I got in from work and so far so good. I actually like the look of the crown thats on them better in person than what I saw in the pictures, plus it covers up the screw holes for the sub. I cant wait to build a box for em and hear how they sound, I think Im gonna build one either just like the one I have or the same size but tuned to 30 hz, If I was thinking when I built the box last weekend I would have offset the sub hole to the side and left room so I could just cut another one out later on but its cool, more experience for me.:graduate:

Quick question though, I have a little "door" that opens up where my armrest is for the back seat, will it be louder/soundbetter if I put the port at the back of the box with the subs facing forward????

PICS!!!!!!!
http://a658.ac-images.myspacecdn.com/images01/123/l_e1c2cfbb0ab2ed4c0dd5ac56a80a8709.jpg
http://a809.ac-images.myspacecdn.com/images01/69/l_ca1dd3b923587ce68f7f85c98cfc6a08.jpg
http://a599.ac-images.myspacecdn.com/images01/96/l_b7e5739b025858848af26ec81225767e.jpg
http://a473.ac-images.myspacecdn.com/images01/80/l_04c99ec703b816e677473a5e0d148c68.jpg