hey um im not really with the audio part of cars but i do have a bit of knowledge.

but im just curious about the sub boxes.
ive seen some with port holes or sumthing (big holes in the box nex to the sub itself)

i was wondering wat its for and if i need it with mine?
cause i dnt have them in my box

Not really a necessary option with box you can have a sealed box (no holes) or a ported box (hole, slot etc)

It's to do with the tuning of the box and where it peaks (is loudest)
Also a ported box in most cases will be louder especially at it's tuned peak.

To be quite honest it's what you think sounds better when it all comes down to it.

Myself I'm a big bass nut especially when it comes down to heavy metal kick drum bass so I have ported boxes but tuned to around the 50hz mark. Mind you these boxes have been used in SPL (Sound Pressure Level) competitions and do quite well.

So I hope that answers some questions for you.

but u can also have clamshell, have one in a sealed/ported box with another one screwed facing it wired out of phase, gives u tighter bass

This type of box you described( clamshell ) is called push pull, one sub pushes and the other pulls when they face each other. This was origanally designed so you could efectivly reduce box volume by half. I have an old car audio australia magazine where they have used this type of set up in a mini to get 24 10 inch subs in it!

haha yer, same thing, i might try it in my car, and 24 in a mini, thats insane

hey scott (saw u in town last night btw) any chance u could scan a pic or ever find a url of it cause that mini sounds off guts.... just wish google provided the answers this time it has let me down again!

i will endeavor to dig out the magazine it was in and have it for you next time i see you. from memory it was built in canberra by one of the stereo shops down there!

ok got another questio if u wanna help.
ive seen subs reversed in a box,(magnet an coil bit stcking out of the box.) can this be done with any sub or specially designed 1?

any sub can b reversed, just need 2 swap ur wire so instead of +2+ and -2- it will b +2- and -2+, on ur sub

well thats wat ive been told from when i ran my old subs that way

kool thnx stitch.... will it make a difference in sound?

i didnt realy notice it cause i didnt swap the wires round than i found out me amp was half dead only 2 channel instead of 4 than upgraded 2 bone crusher amp and sound off box

fair enough
thnx heaps m8

i shouldnt make much difference.

you only need to swap wires if your flipping one sub really, its more important to have all subs in phase with each other, eg, both pushing at the same time.

so if you flip one and not the other, you have to have them wired opposite, if they are both flipped, you can swap the wires on both, or just leave them. I had tried both ways when i ran my kickers invert mounted and didnt notice a difference.

just play around with it and see what works best for you, and have fun

but for sound off inverted is not as good

TM's CraZy TaXi wrote:

but for sound off inverted is not as good

why is that?
won't the sub still be moving just as much air, is it due to their being less surface area on the inverted side of the cone? i would think that this would change again if the box was ported, cause you would have more air pushing inside, which would come out the port?

just curious, cause i never actualy got round to trying my kickers both ways, i just know they worked well inverted in a ported box.

just curious.

A push/pull setup where the two subs face one another is called a isobaric enclosure, a clamshell is a wall where the baffle is shaped like a open clamshell which allows the fitment of more woofers,

when you invert a sub you lose about 15% of your cone area from the magnet and basket blocking that area.

jozlod the reason your subs would have sounded better inverted is the extre area you had in the box from the magnet not taking up that space and it would have been tuned i little lower.

yea, hlaf to reason i flipped them was cause i cut some off the top of the box for it to fit, so i flipped them to try and re-claim some box volume, but i never really tried them mounted normally anyways.

i just thought that maybe the extra cone area pointing in would make more air go through the port, as there is extra cone area firing into the box, but im not sure.
cheers

its all good we all have to learn new things from somewhere like I learn new stuff pretty much everytime I touch the car.