Sub box help

[fraz]

After reading this article (http://www.overclockers.com.au/article.php?id=90128) on OCAU i decided to give it a go.

I have aquired an amp that will make 100wrms @4 ohms @12v
i currently have a 12v supply but will look at getting a 15v one if i need more power.

im after some floor shaking bass to go with dvd movies and the like. It dosent have to be really loud, just give a a bit more punch to my stereo.

What kind of sub would suit?
I have looked a bit and most car subs are around the $200 mark (10 inch) with reactor being the sheapest and also the crappest by a long way.
Has anybody tried one of those jaycar subs??

The pics show the enclosures im considering. Which would suit my needs??

cheers

[fraz]

sealed box

[fraz]

ported

[fraz]

Bandpass enclosure.
the one on the left is the one im looking at

[shag]

There is a lot of theory to know if you wanna make the enclosure just right for the driver. Using a different brand or model woofer in a particular box will work but they will all sound and perform differently even tho they are of the same size. This is because of the differing properties of the drivers.

Do you have a program to help give you some idea's of box and port sizes for different drivers?

I could prolly point u in the direction of some if you like.

[mird-OC]

the carbon jaycar woofers go hard, i've seen em in action - well worth the dough.

a properly tuned bandpass enclosure will always perform better than anything else - the problem being that tuning them is a bit of an art. there are some designs for adjustable bandpass enclosures out on the www which ease this issue to a certain extent and apparently work very well (i'll see if i can find the links for you).

the other problem being that in a bandpass enclosure the driver can be distorting quite badly (from either clipping or even the driver bottoming out), but you often can't hear it, so people end up wrecking their subs. care and attention is all that's required tho.

sealed enclosures are the simplest to design/build and are the most forgiving of mis-tuning. ported enclosures are a little bit trickier but tend to go a bit louder and have an extented low-end response.

as shag mentioned each driver has it's own unique characteristics and should include a sheet of information with various values used to properly tune an enclosure for that particular driver. there are several programs available that use these values to simplify enclosure design and tuning. google should shed some more light on this if you need it.

[shag]

i'll just post links as I find 'em ;)

http://www.speakerbuilding.com/

[_N_]

I'm thinking of selling my two 8" subs in a box with no amp,

they are loud enough to shake the house with no distortion,
basically, too loud, if you are interested?

also, DSE use to sell 10" 250W subs for 19$, they are good, and I will box one up later on, you can find them on trademe for 40$+

once I get more time, i will tell you more, just got back from the rally and got heapsof other stuff to do

[_N_]

those jaycar ones seem expensive, I can't access the site, but looked on the CD.
here are some prices from local auckland shops

Fusion Encounter 12" Sub - 150$
Magnet Structure 80 Oz
Power Handling 400 Watts
Voice Coil 2" Kapton SVC
Frequency Response 24Hz to 3kHz

Pioneer Tsw304c 12" 600 Watt Sub - 200$
Frequency Response: 18 – 2,000 Hz
LRF (Lowest Resonant Frequency): 23Hz
1,240g Ferrite Magnet

Boschmann 12" 500W Subwoofer - 155$
12" 500Watt Subwoofer
Kevlar Cone
500W peak output
Frequency response 35Hz-3500Hz


If you make a sealed box which is large enough, you will get loads of bass coming out and they will go hard.

If you wanna put it into your car to show off, then you need to go that extra step further.

ALso, when you make the box, make it so that it's strong enough for you to stand on it and jump on it without breaking.

And another important factor, make sure your connections are done properly or your sub will sound real crap,

[mird-OC]

the jaycar carbon subs aren't the cheapest you can get (although they are still pretty cheap), but they're also not the nastiest. from experience i can tell you they outperform (SQ wise) most entry level subs out there.

but there is a lot out there to choose from in the sub $250 range.

[fraz]

thanks for the info.

N - how many watts were you putting into those subs??
my amp will put out 10o@4ohms. At a stretch i could hook up 15v and it puts out 150w. It dosent like 2ohm bridged but can do 75x2 @2ohm 12v
Im keen so give me a price and ill get back to ya

Otherwise i think ill go with a bandpass box and 10inch. I have a mate who has done a sound course so ill get his help for tuning and stuff.

[_N_]

I'm using that Jaycar 55W@4ohm one which runs at about 60°C with a big heatsink, i put it on trademe, and it went for 73$, but the guy still hasn't come to get them or pay for them, probably won't at the end,
yeah, the box is big and strong, not carpeted or anything like that, and the subs are allright. I would sell them to you for 50$, you live somewhat close to me? I could probably drive up to your place one of these days,

[fraz]

hey N, cheers for those subs.
Took me a couple hours to hook up the amp and seal up the joins in the box.
The neighbours have already been round complaining :D

Only one problem- i NEED more power, the amp can easily drive these and so i was wondering if anybody has 1 or 2 10 inch subs for sale??

Cheers