ok ive got heaps of info on what is required when considering sub box building/design. if enough people want i can put together a serise of tutorials on how 2 build/design all the of the 6 major styles of automotive sub box.

1 infinite baffle
2 sealed enclosures
3 vented/ported enclosures (reflex box)
4 banpass enclosure (4th order banpass box, asymmetric banpass)
5 double reflex
6 ABC box (ment 2 be the magic sub box)

if enough want just say yes and ill do a BIG post each week (one style per week or so) and try explan all i can on each design. all the do's and dont's and the different chareristics of each enclosure with expected results...

cheers
nathan

yer sounds good, not my thing but im sure its worth a read

sounds good lookin forward to 3 vented/ported enclosures (reflex box)

would be interesting... im looking at designing my own box soon so it could be good.

that sounds like a mighty fine idea. im thinking of building a box for 2 12ch subs or just buying them. but i know i can get mdf for free

give us a yell if you need some info on the "she'll be right" box, in a king at building them

I wanna know what the magic box is...

yeah sounds like a good idea. I would read them

Yeah good idea man, I'm making one now so I'll hold off until you post up the info. Cheers!

yeah mate sounds great and food timing too have way through doing my mates camary i take some pics on doing a false floor +writing on ths one........ going to be alot of rum used on this job

1...2...3..." Hell Yeah"

Yep, should be good. I can link these guides from my Tutorial

TRD Rolla

topic 1

Infinite Baffle



infinite baffle enclosures are the simplest from a design concept. the principle of IB design it the seperation of the front output of the woofer from the rear output of the woofers. one of the advantages of this design is the low resonant frequency of the IB system. this low RF allowes the system to have a very good low frequency extension. another advantage of an IB design is the little amount of boot space needed for this application. for this reason IB designs are popular in cars where the boot space is small but there is a need for big bass...

one of the main disadvantages of this application is the REDUCED MECHANICAL POWER HANDELING of the speaker. this is due to the fact that the inclosure is actually the whole boot volume and the air in the boot is not able 2 help the mechanical suspension system of the woofer, for this reason not all woofers are suited for IB applications.

it is a common misconseption that IB enclosures are the easiest to construct, this is not tue as maximizing performance in this type of enclosureis quite dificult and time consuming.
Maximizing the performance in a IB system you must minimize leaks and maximize the sturdiness of the baffle....

ok so in short an IB enclosure is putting a sub in the parcle tray and using the boot as one big enclosure and attempting to seperate all the air either side of the tray, same principal is used when placing a sub in the ski-port in some sedans and using the back seats/parcle tray as the dividing wall and the boot as the enclosure.

also this type of enclosure means u cant feed buckets of power 2 the sub cos its not being helped by the box and will be worked 2 hard if u do appily 2 much power.

you will be suprised how many installs come out of brisbane car sound like this, if u feel air leaking from around the plate ur sub is fixed 2 then this is the "box" that u have got...

hehe... Brisbane Car Sound...lol

Awesome info. mate, keep em coming

TRD Rolla

Are you gunna do Isobaric boxes?

Ferdie can you do me a favour and post a good reason why pre fab boxs dont work in commodores PLEASE

i am tired of trying to explain it

When are you going to do a tutorial on building a hairy, wet box.
I'd love to make one but dont know where to start.

its al common knowledge ..banpass rnt very good boxes mostly cheap market subz that only look good with no oonf .. ported and sealed enclosures r the go depending on the subwoofer and the nature its best in.... 70% are sealed sum ported enclosures giv a much louder and brauder sound than a sealed ..building a box for ur sub is very hard thats y its best to buy the sub in its custom box ..with building u need the right timber u need to know the volume of the box etc etc ne ways ill shutup now

Put your box and fire it into the right back corner it will load up well, otherwise the box is wrong for the sub???

Back left corner me thnks... about a foot away from the tail lights worked for me..... hahahahha!!!! Also that magic box is a load of poo... and a waste of MDF... Bandpass boxes arnt too bad at all for SPL... a mate of mine uses a BP box in his astra which currently holds one of the DB Drag class records. The problem is they r only loud over a certin frequency range with little output above or below!! But if u can tune the BP box to hit at your car resonant frequency then LOOK OUT

this one has been a long time coming.....

Sealed Enclosures


sealed enclosures, also referred to as acustic suspension enclosures, work by having the speaker installed in a totally sealed body of air in whis the internal pressure of the air aids the cone while it moves creating the sound.

the enclosure acts like a spring and helps control the woofer by limiting the cone motion below the resonant frequency of the enclosure (Fc). the benifits of a sealed enclosure when designed properly is excellent mechanical power handeling, low frequency roll-off rate of 12 dB/octave, and ease of construction. the disadvantages of the design are the trade-offs between power handeling, maximum output, transient responces and low frequency extension.

the relationship between the size or volume of the enclosure and the Theile-Small parameters of the woofer determine the overall performance. the (Qtc) reperesents transient responce,power handeling, and low freq extension. with low (Qtc) values the transient responce and low freq responce is good but the power handling is less. with high (Qtc) the transient responce and low freq is poor but the power handling is much higher. the used car audio range for (Qtc) is 0.5-1.5 for acceptable results.

when an enclosure is too large (close to the 0.5 Qtc range), the suspension of air in the enclosure no longer assists the mechanical control of the woofer, and thus the excursion of the woofer can be reached thus damaging the woofer and sounding shit...

i have heaps more 2 type on this but i feel sick and am going back 2 bed.....

will finish this all as soon as i can get round 2 it...

thats a mad idea, do it for sure.