Q: sub box size?

[JJCRU23R]

yes as topic description asked...

but more specifically, the sub im expecting to recieve next week requires dimensions of " .33 - .75 cu.ft." (sealed box).

does that mean a minimum of .33 cu. feet and maximum of .75 cu. feet ..?

just checking am i correct on this assumption?

and since its .75cubic feet max. area inside the box, if i was to make the box any larger than what was recommended, will the sound turn out dreadful or is this a case of the more space the better?

also.. whats the best/easiest way to measure cubic feet?!

maths specialist please i need your help!

Edited September 8, 2006 by JJCRU23R

[BigBum]

Basically to answer your first question, yes. Build your box within that range and you will bring out the best in those Solo-barics.

All I know is if you create a box with a volume of less than .33 cubic feet for those kickers, your bass is going to be very boomy and non responsive. A box with capacity higher than .75 cubic feet, I'd assume the opposite?

To measure cubic feet in terms of litres: Cubic feet * 28.32 = Volume in litres

e.g .33 * 28.32 = 9.35 Litres.

You get the drift ;)

Also check out a program called WINISD (bit hard to use), but is great for creating your enclosures as it calculates everything for you.

[JJCRU23R]

that program is hektic! too damn technical i dont know what the hell kinda information they want me 2 fill in! definately not for newbiez in the subwooofermaking business :/

anyhoo i think your info helped me out a lot more than that program, too tired 2 figure it out 2nite... maybe tomorrow.

im planning 2 make this outta fibreglass btw.

i learnt how 2 measure litres in highschool, 4gotten it since then. plus this sub is gonna be moulded into the right side of the boot so yea snug fit, and not a regular box shape.

seen quite a few tutorials on DIY fibreglass box's but they ddindt mention measuring the cubic feet 4 optimal bass.

like most other things in life i want to get this thing done right the first time so i dont wanna take chances on makin it 2 damn small

[Azza]

I havent seenthe program that Brandon just recommended but I use to use a program once called Name...which is frigging hard to find now.

All the crappy numbers and things you have to enter are ones which will be supplied on the data sheet with the sub when you get it.

Essentially, what I have found is that if you make your box too small, then you lose response, and the sub, although sounding 'kickiy' may lose its effectiveness is preoducing good solid bass.

As Brandon said if you go the other way, you have the opposite effect, the sub will end up producing aheck of a lot of low end bass, but you will lose dB and response.

The sub itself works on resistance, being the amount of air mass it needs to push. When it is pushing the right pressure of air mass, it produces the signal you then hear.

Depending on what sort of install you are going for. If you are just wanting a sub in a box in your boot, then most audio shops could sell you a pre-fab box in approx the size required. If you are getting a full on install, leave the calculations up to the installer (thats what you are paying him/her for).

I hope I have provided something useful....

[JJCRU23R]

yea azza it makes a lot of sense, but im not gonna pay 300 for a custom install when i can fibreglass it myself :P

i just gotta make sure its the right size!

with the custom moulded box that silvabullit has, it doesnt let your seat recline all the way back. i plan on avoiding that problem by moulding the fibreglass with the seat reclined. this may result in the box being wider, which means less boot space, but since his amp is a 12" and mine is an 8... i think itll even out since mine is a helluva lot smaller and requires much less room.

is there any other factor i missed out here? anything else i should consider?

oh yea i plan on placing the amp ON the sub box, probebly above the sub. is this generally a bad move? after all, the sub is only 8inch square. and should have plenty of room.

i also did that on my 1st sub box which had 2x 10" weconic subs in my old landcruiser, didnt have a problem. but is this not a good thing 2 do?

[Azza]

Dude, throwing the amp on the sub box is never going to cause any operational issues. The only issue I personally ever have with it is that it means you need to run power, remote and input cabling all the way to the boot. Installing it under your front passenger seat, while may take a small amount of time longer during install, will mean you will use about 3 meters less power and input cable, you then only need to run your output cable from there to the boot.

The other bonus is that should you need all your boot space for some reason, it is far easier to remove the sub box with only speaker cables to disconnect.

When I had my amp in the boot, my auto-electrical mate and I messed around with an idea of using a combi plug (similar to a trailer type plug) so make this easier, but it never really worked so under the seat it went.

But, at the end of the day, its your choice.

Fibreglassing the box yourself may indeed cost a lot less than paying someone, unless you keep messing it up and having to re-do it... I think the box that SILVABULLIT has is around $300 - $400 mark.

Bear in mind though that time, patience and beer is what will cost you in doing it your self....

Again, your choice...

I have attached 2 images of my sub box for you. Its nothing flash, but it looks neat and tidy and together, there is only $140 odd bux worth in the boot...

As to any problems slightly warping the size to accomodate the recline, I couldnt see any....as long as you do the maths correctly....

[JJCRU23R]

this is my badly drawn artists impression of the sub box...

thought i may need a visual aid on this 1.

yea azza youre right bout the cabling... i encountered similar problems with my old car n the sub box&amp...

thats another design problem im goign 2 have 2 address b4 i even mix the fibreglass catylist with resin.

:P

Edited September 10, 2006 by JJCRU23R

[Nunga_08]

Are you a fibreglasser by trade? Or just a general handyman?

If none of the above, I'd spend the $300-$400 you reckon it'll cost to get the sub box made professionally. People don't become Car Audio experts for nothing; young guys spend years in the business honing their skills. Fibreglass is pretty hard to work with, too, and it might take a few attempts to achieve the best result.

With the volumes you've given, I'd probably aim for something smack bang in the middle; that way you're using the optimum box volume for tight and punchy bass, and some decent SPL at the same time. If you move either way from that figure, you'll sacrifice one or the other (as has been said previously).

[JJCRU23R]

Are you a fibreglasser by trade? Or just a general handyman?

jjcru23r = jack of all tradez, master of none :P

With the volumes you've given, I'd probably aim for something smack bang in the middle; that way you're using the optimum box volume for tight and punchy bass, and some decent SPL at the same time. If you move either way from that figure, you'll sacrifice one or the other (as has been said previously).

what you mean smack bang in the middle?

you mean sub placement in the middle of the box, right?

OR are you referring to the range of area the box requires?

'...based on the required dimensions of '..." .33 - .75 cu.ft." (sealed box) '?

[Nunga_08]

Range of dimensions ;)

[JJCRU23R]

Range of dimensions ;)

thought so. yea i was planning on doing just that - especially coz i still need space in the boot, but id like the best sound possible out of this sub.

just cos it says max of .75 cu ft, dont mean im going 2 build it that big

[MT]

im not sure where u are located, but a shop down here in canberra made a custom sub box for mick0082 to go in the back of his sportivo. looks sweet, sounds orgasmic, the back seats still recline and the spare wheel and tools are still accessable. just so u know ;)

[JJCRU23R]

im not sure where u are located, but a shop down here in canberra made a custom sub box for mick0082 to go in the back of his sportivo. looks sweet, sounds orgasmic, the back seats still recline and the spare wheel and tools are still accessable. just so u know ;)

locatedd in western sydney.

how much did his box go 4?