well i know there is set calculations on how big to make your sub box with knowing the size of the boot, sub rms and amp rms

so my question is does anyone know how to calculate it ???

i googled alot, wasn't good at getting correct calculations and conversions so i bit hte bullet made one a lil bigger than the one i had already (bought it and it ran great) and its running fine.

what sub(s) you got?

What sub what amp and what kind of music you listen too???

Kenwood KFC-W3514DVC
Woofer Features
300mm Titanium Coated Cone Woofer
Removable Gasket for Reverse installation
Rolet Terminals
Easy Smart DVC Terminals

Enclosure Size
Sealed Box: 1.2 cu.ft
Ported Box: 1.7 cu.ft

Peak Power Output
1500W

Rated Input Power
380W

Specification
Sensitivity: 93dB at 1m
Frequency Response: 25-800Hz
Impedance: 4+4 ohms
Mounting Depth: 172mm
Magnet Weight: 1,200g

but its running of a 200w 2channel amp

need a upgrade

listen to mostly rnb, hip hop type

Your sub/amp wattage (RMS) don't really have anything to do with box size. It's the technical specifications that will dictate whether you should go sealed or ported, what size, what frequency, etc.

I used a program called WinISD (http://www.linearteam.dk/default.aspx?pageid=winisd) to design my sub box. Give it a download and have a play around.

Just as an example, if you want to stick to the recommended sealed size (1.2 cubic feet (assuming gross, not net)), you could make a box 35cm wide / 35cm high / 36.8cm deep (if you're using 16mm MDF).

The RMS that you put into does play a part in the whole equation of building a sub box,

Is there a reason you wont to build the box, want it to be ported to hz, want it the conform to the shape of the car to maximise usable area????

Hate to say it but the clarion ported boxes that you get from autobarn aren't such a bad thing, haggle abit should get it for $70

And your amp, you will need to wire the sub up to 8 ohms as i'm sure your amp is not designed to run 2 ohm bridged.

Im using the RE audio website box calculator for my box that I will be building soon. You just input the dimentions of the box and then you adjust the port size to achieve the tuning frequency that you desire.... It then gives you the specs for the sizes of wood you need to cut out to make the box! Easy peezy!

I think it may only work for ported boxes though...

PS: That amp will be seriously underpowering the sub.... (will be putting out around 100rms bridged as opposed to the 380rms which is needed)

The RMS that you put into does play a part in the whole equation of building a sub box,
How so?

ok guys how the fudge do i wire this thing, do i need 2 mono's, each runing to the separte plug ins? or can i use a 2 channel and brindge the sub

and another thing wat is better lower ohms (like 2 ohms) or higher ohms (like 4 ohms) ???

what size wattage amp would i bee looking at

and another thing wat is better lower ohms (like 2 ohms) or higher ohms (like 4 ohms) ??? do i need 2 mono's, each runing to the separte plug ins? or can i use a 2 channel and brindge the sub
Most amps produce a higher output at a lower resistance, so I guess you could say that lower is 'better'. Since yours is 4+4ohm, you can wire it up for either a 2 ohm or a 8 ohm load.

You just need to make sure your amp can handle a 2 ohm load. Like khorne said, a basic 2 channel amp won't be able to do it. Most monoblocks will handle a 2 ohm load fine.


what size wattage amp would i bee looking at
Ideally something that would produce about 400w RMS at 2 ohm. Having a quick look through Ryda, something like this (hhttp://www.ryda.com.au/Clarion-APX1301-Mono-Block-Car-Amplifier-p/apx1301.htm) would be fine. Its only a cheap sub so you don't need anything extravagant. Response used to make a cheap monoblock IIRC, but all I can see on their website is a 1000w monoblock (which is way overkill).

How so?

The more power you put into a sub the more you make it exert, so buy reducing the size of the box helps to control the sub and stops it from over exerting, but you only start to do this when you push over the double rated power,

i have a customer that put 3500w-4000w in a pioneer ts-w307d2 and it survives, until he does something stupid like puts a 20hz tone throught it for 15secs

what i would do first is measure your boot so you can maximize space in your boot while still meeting specs. Since you listen to hip-hop/r'n'b i would definitely recommend a ported box probably tuned to 38hz ~ish. You can build your box on this site www.reaudio.com/speaker_box/LPort_Box_Calc.html. However before you do decide for sure ported or sealed box, you should note the QTS of the sub it self. Some subs are better in a sealed box. It should say on your spec sheet which came with the sub. By the way, be careful with the sub/amp combo, with most dual voice coil subs people usually run them at 2 ohms, however beware of the amp (i.e if it can handle 2 ohms). if you could tell us what amp you have and its specs it will probably be easier to help you out.