DJ SprinklesNJO

let me just ask this. if i want 6 subs in my truck, they would have to be 12ohms each wired down to 2 ohms mono right?

i was looking at this one type of sub and it said it had a dual 4ohm voil coil. so thats only 8ohms right?

i need to come across a 12 ohm sub if what i said above is correct.

any comments please.

BananaGS

correct me if i am wrong, but I have not seen a 12 ohm sub ever before. Beside, why would you want to do that?

you will not be able to sell them individually since no one can use them in individual or dual set up hee hee.

look like you want to build the system for show, then it would make sense to get 3 amps to show also?

6 sub, 6 ohm each, use 2 mono amp, 3 sub for each amp (2ohm).

or 4ohm each, 3 mono amp, 2 sub for each amp (2ohm).....


ye, 6x12ohm in parallel will give you 2ohm, but need 6 times the power to drive to get to the same level of a single 2ohm sub/amp

BabaBooey

You could wire the VC's of each DVC 4 ohm speaker in series. That would give you an 8 ohm load. Then wire each speaker in parallel. You will end up with a 1.33 ohm load. Plenty of amps can handle that load well. You could run an overly stable amp that puts out max power @2ohms, one that puts out max power at 1ohm and lose a little bit of power, or an an like the JBL1200.1 that will put out the same power anywhere between one and two ohms. If you bring multiple amps into the picture, you've got a whole new ballgame. 6 subs sounds like you're planning on competing, and if that's the case, I see no reason to utilise only one amp.

DJ SprinklesNJO

oh boy, all good points, but to cear it up, its not for show, just plain looks. i just recently bought an audiobahn 3201x amp. 840watts rms mono 4ohms. and a triple 12'' audiobahn sealed sub. the new one with black leather. ok so this is why im thinking there are 12ohms subs. my triple 12'' sub box is 4ohms. so what gives? oh and i dont want to buy another amp.
ps if i do decide to get another three subs from another box, i will have an empty triple black leather sub box for sale. brand new. you can see it at audiobahninc.com

lisnup65

Dual 6 ohm subs are common. Series the voice-coils for a 12 Ohm driver. This was were JL Audio shinned a few years back.

BabaBooey

I'm still unclear as to whether he wants 3 or 6 subs, as well as whether he's getting another box (make sure all the subs share the same airspace, i.e don't put 3 in a 4ft^3 box and 3 in a 3ft^3 box), else you'll get different frequency responses/Qtc, maybe some cancellation.

DJ SprinklesNJO

bababooey, i want 6 subs! is that clear, lol also i understand that i need all the same air space. with that said, can someone help me with caulating how to determin air space. what is the mathimatical formula>? i knew this a while back, but forgot it.

DJ SprinklesNJO

do you mean dual 6ohm voice coil subs? is that how there are such things as 12 ohm subs?

then to answer bababooey again. if i cant find 12 ohm subs sold individully, i would go out and buy another triple 12' sub box, and then just take the speakers out of it. so then after i would have an empty box sitting around. (for sale) lol

lisnup65

Yes!!! Dual 6 ohm voicecoils! The design was simply. To gain more SPL meant more air displacement. To get more air dis, you needed more cone area or a hella lot more amplifier power. JL's design was to use 3 dual 6ohm V-coils for a then industry standard 4 ohm mono load. Thus doubling the subs to 6 and wireing them is parrael will yield a resistance of 2 Ohms.

lisnup65

LxWxH minus the wood / 1728 will give you the internal airspace before the speakers.

I.E.
An enclosure that is a perfect square 1 CU' will have 12x12x12 of internal airspace. External with 3/4" wood will be like this: 13.5x13.5x13.5.

The math shows how important it is to subtract the wood.

12x12x12=1728/1728= 1 Cu'

13.5x13.5x13.5=2460.375/1728= 1.4238 CU'

GL

BabaBooey

JL's dual 6 ohm config was just a clever way of getting people to buy three of their subs, IMO...

First of all, I can't think of any modern 12ohm SVC subs. It would be a very stupid move for a company to do that.

No offense, but I still don't quite understand how many boxes you have, if the boxes you have are prefab/custom made/one of each, etc...

Someone may find a way to do it, but you're not going to be able to find 6 subs that will yield a single 4 ohm load. It's just not something common to run 6 subs with a single amp. I think you may want to look into getting another amp, or if looks are THAT important to you, a sub setup that looks good using fewer than 6 woofers. In my opinion, a single sub setup can look badass. Just get something like an Eclipse Ti/IDMAX/Brahma, mount it with the vent facing out, and use creativity to make it look nice. Hell, for the money you would spend on six subs, you could build a badass looking plexi box.

DJ SprinklesNJO

lisnup65
how would you caculate the air space if the box wasnt perfecty square. lol oh yea thanks for the first equation. also in that equations do you always devide by 1728? some of it was unclear.

lisnup65

1728 = 1CU' thus you always take a lxWxH/1728. If the box is not square nor rectangle, but rather has a triagled shape due to a sloped front/rear, etc. Then you must look at the enclosure in 2 parts. Take the square area and figure the volume, then take the triangle area and figure as a double of its self so it has 6 sides and not 3. You then take the area figured by the normal calculations and divice by 2. Add the first volume and the halved volume for your total volume. Im sure I lost you, but its simple mathmatics.

DJ SprinklesNJO

oh yea, duh that makes sence. it is simple mathematics, but you did loose me alittle in ur explanasion. now all i have to do is figure out what the dimensions are of my box im plannin on making. its not just one angled wall. there are many. the front row of 6 subs will look like steps. laying down. i have a drawing of it in Paint program on the computer, but i dont know how to post it in here. i can however email it. so if you want a pic of it, for a better understanding of it, let me know. also can anyone tell me how to post pics of drawings please.