[turboxl]

Hi guys i know its been a while but ive been very busy with the transition work and the transition into uni and what not. I bought this sub off ebay, here are its stats as posted.

Product Description:
• Aluminum Voice Coil Former
• Extended Pole Piece
• Vented Oversized Back Plate
• Flat Spider
• 120 oz. Double Stacked Strontium Magnets
• Power Handling: 1000 watts R.M.S.
• Frequency Response: 18Hz – 500Hz
• Efficiency: 96.4 dB
• PHAT 1.75" EPDM Rubber Surround
• Spun Aluminum 1-Piece Cone
• 3" 4-Layer Edge Wound Voice Coil
• Dual 6 Ohm
• 3 Ohm or 12 Ohm Operation
• Mounting Depth: 5-5/8"
• Cutout Diameter: 11-3/8"
• Multi-connect Lug Lock Terminals
Subwoofer Specifications:
• Subwoofer Size 12"
• Impedance 6 ohms
• Dual Voice Coil Yes
• Peak Power Handling 2000 watts approx.
• RMS Power Handling 1000 watts
• Surround Material EPDM Rubber
• Sealed Box Volume 0.5 - 2.0 cu. ft.
• Ported Box Volume 1.3 - 3.25 cu. ft.
• Sensitivity 96.4 dB
• Frequency Response 18 - 500 Hz
• Top Mount Depth 5-5/8"
• Cutout Diameter 11-3/8"

Sorry its so long. What i really want to know, is the difference between a ported box and a sealed box and how performance varies and secondly i was hoping for some recommentdations on which way to go (i.e. ported or sealed).

Cheers for any info. Anand. -

 

[meee2yo]

people have been happier running the audiobahn alum12 in a sealed enclosure. small sealed enclosure, like a little less then 1 foot.

 

[meee2yo]

0.85 cubic feet per sub up to 700 watts

.75 700-1000 watts

do not feed that sub more then 700 watts. Great sound quality if you do not build the box to large. it goes really really low in .85, not as low in the .75 but has more power handling. post up pics! Sorry, had to go through my notes on this sub to get the info. While you can do a ported box, nobody is happy with the sound from it (from my experience) and in a sealed enclosure it's the best sub for the price (imo)

[Edited by meee2yo on Mar 7, 2006 8:31 AM]

 

[LilTimmy]

I like sealed boxes I think subs have better response in smaller sealed boxes. I like meee2yo's .75box, maybe a little bigger but either way it would work. Ported if built right has a lot more bass, so it depends what you are looking for, the type of music you listen to and stuff like that. If you are not sure which way you want to go then build a larger sealed box to try to split the difference.

 

[griffin60]

I made a simple sealed box for one of my friends it has .8 cu. ft. volume and pounds just a little less than my JL 12W7.

 

[turboxl]

Ok well heres a link to the same sub i am getting, from same seller and everything. Only difference is i didnt do buy it now so i got it at $227.50(AUD) including P&H.

http://cgi.ebay.com.au/New-Audiobahn-Alum12N-1000RMS-Dual-V-Coil-Aloie-Cone_W0QQitemZ5852636069QQcategoryZ3292QQtcZphotoQQcmdZViewItem

And yea i listen mainly to dance, techno, trance etc... Also a bit of Rnb. So yea im thinking sealed box then, only question is how big. And also wat kind of amp should i use to power it?

I currently have an amp with these specs.

Power / channel @ 4 Ohm 14.4V 150WRMS x 2
Power / channel @ 2 Ohm 14.4V 255WRMS x 2
Power / channel (bridged) @ 4 Ohm 14.4V 500WRMS x 1
Signal/Noise ratio >90dB
Input sensitivity 200mV - 5V
Low Pass filter 50 - 500Hz @ 12dB/octave
High Pass Filter 50 - 500Hz @ 12dB/octave
Pass Through RCA Yes
Remote level controller Yes (Wired)
Dimensions 340(L) x 258(W) x 50mm(D)
Finish Brushed Aluminium

Can that be used to run it?
Cheers, Anand. :lol:

 

[187sks]

While I have no experience with this sub, I would think you could run it off of that amp with no problem at all as long as it's a decent amp and actually putting out 500 watts RMS. I'm running a 15" Solo Baric S15L5 off of an amp of about that power rating and I am very happy.

Also I vote sealed box as well for what you listen to.

 

[turboxl]

Ok just to make sure. What im gathering is for my application... a .75 cubic feet sealed box is the go? Also is there any advantage to reverse mounting the sub? I assume this effects the dimensions in the box? as there is less inside it then. Cheers for any info.

 

[solo-baric]

the box really depends on what music you listen to and how much space you have to work with and if you really know what your doing. Sealed boxes are more forgiving then ported.

 

[meee2yo]

with 500 watts you would go with the .85 sealed,

that's really dependant on the sub, that is where trial and error come into play. .85 will make it sound the best.

if you want the sub inverted, just wire it backwards.

 

[turboxl]

Ok sweet ill look to get/make a .85 box then. Also when you say reverse wiring, do you mean + from the amp to - on the sub and so on? And also ive got a preexisting single 12" sub box from before i upgraded to 2 12"s. I was wondering how i go about measuring it to see how big it is incase its the right size i need. Thanks for the help guys. :lol:

Cheers, Anand.

 

[meee2yo]

well, if you plan on having the speaker in the box backward, like the basket facing out, then wire positive to negative and vise versa, so the sub is still in phase.

you can do this with no problems with the alum

also, the math equation for airpace is:

h" x w" x d" divided by 1728 = cubic feet

so
12" x 12" x 12" = 1728

1728 1728 = 1 (cubic foot)

angles make it harder, but not really, square it out. first measure the square part, then the angled pard as a sqare and divide by two.

 

[turboxl]

hmm... so i gess my maths teach was right... there is a use for maths after school... :lol: Thanks heaps guys. Ill let you know how it goes.

Cheers, Anand.

 

[turboxl]

Ok guys... well i got a hold of my old single 12" box. Its a wierd shape that required 3 m'ments to get the area of the side. Well anyways, The total area of the side was 128.7 Square inches. So i would times this by the width right? i.e from one of the side faces of the box to the other. (this was 15.3in)... This gave a total of 1969.11 cubic inches.

Then i divide that volume by the magical number... 1728 to get it in cubic feet, correct? This equals 1.1395 Cubic feet. Does that sound like a correct volume of airspace, including the sub if i mount it normally, considering i am aiming for .85 cubic feet?

Cheeers, Anand. :lol:

 

[meee2yo]

well, it will not be .85 after you mount the subwoofer.

I am looking for and cannot readily find, is the VAS of the driver. This tells you what airspace the driver takes up so you can subtract that from the volume of the speaker box. looking now.....

 

[solo-baric]

dude build your own box to your specs! i've posted a calculator on here before. there are plenty on the net.

 

[turboxl]

yea ok looks like ill be buildin my own box then. I dunno, if it has a vent in it does that make it ported and not sealed anyways? Cos this one had one. And yea, im sure it'l be a good learning experience building my own box :lol: Just as a side note, when building a sealed box, form your experience, wat are the main points to look out for. E.g. type/width of wood etc...

Cheers, Anand :lol:

 

[solo-baric]

ok here is what you need to build a box.

one sheet of MDF 3/4 inch thick
one tube of liquid nails
i box of screws (may people use drywall screws you know the black screws. I've have some good and bad eqperiences with them. but it's up to you. just make sure the screws are about 1 1/2 inches long.)

Remember measure twice cut once.

 

[turboxl]

ok thanks for the info, ill get around to buildin it when i know how long the sub will take to arrive.

 

[LilTimmy]

I normally get a few cans of rubberized undercoating(or you could buy the expensive stuff from a car audio shop) and spry it on the inside of the box when you are done building it, this should help to make the box sealed incase you missed some little holes with the liquid nail.