Bandpass Box

[Jet-Lee]

http://www.decware.com/whorn.htm

I'ma give one of these a try and let ya'll know how it goes.

EDIT - Because of space limitations, I will be doing this one instead. It should still put out awesome.

[Jet-Lee]

no input?

[PaulD]

prefab bandpass boxes usually sound pretty bad unless you get lucky. They must be carefully tuned to the speaker and the car, much more than all the other box types.

[Jet-Lee]

I'm makin' it myself. Got some plans laid out in 1:1 scale, so it won't be too difficult.

[PaulD]

well good luck with it ....... the other problem with bandpass is that the speaker is totally enlosed, you can't actually hear the sub itself - so you can't when you are overdriving it. Makes the speaker easier to blow because of this.

[Jet-Lee]

I'm a step ahead of you, Paul. I currently have the subs in a regular sealed box. I have them set LOW LOW LOW, and they still pound. I have had them turned up on several occasions and have yet to make them overdrive. I plan on leaving the amp at it's current setting, and I have tested the subs up to an undesireably high level with no overdrive and marked it. This will be my limit when I cannot see them. If I'm not happy with them at that point, then the box goes.

[bumpinstang77]

It doesn't matter what they are like in a sealed enclosure. Subs react way differently to different boxes, reguardless of power.

[Jet-Lee]

I know this, that is why I have tested them up to a certain point. If they don't perform well up to that point in this new box, then I'm scratching it.

[PaulD]

just make sure you have a good (steep) lo pass filter on the amp. In a ported box, the speaker is essentially unloaded below the tuning frequency - so it doesn'ttake much to blow them.

[CBFryman]

hehe, my sub looks pretty at 18Hz...

anyway, in my experence it doesnt take much, even in a 4th order, to get some poundage. i dont know what vehicle you drive but 150w + Alpine type-R 10 + 6th order + CRX= uber wangage...

[Jet-Lee]

I don't under stand "order's", except "A number 2, steak, no tomatoes, and a pepsi."

[CBFryman]

for simple's sake...
a 4th order bandpass enclsoure has 2 chambers, one is sealed and of a certian volume to have the cone react in a certian with the other which is ported and "tunes" the waves.
6th order both chambers are ported and both the front and the backwaves are working in unison by being tuned to different frequicnies (the same frequincy would cause cancelation). 4th order is efficent but 6thorder is even more efficent because it uses front and back waves. its why a ported enclosure is more efficent than a sealed one, it uses both front and back waves.

there are some sort of defined rules of thumb for a 4th order enclosure. however 6th order is the luck of the draw in most cases. some anecho curves can be "predicted" through calculation but i dont think they can be predicted as acurately as with 4th order bandpass, sealed or bass reflux (ported). they take a lot of time and effort and trial and error but when yo uget one right it takes little power to get loud and they take up less space than a Transmission line (snail shell/more precicely tuned quarter wavelength enclosure) and has similar if not better efficency and takes up a LOT less space than a bass horn. but is not as efficent as a bass horn (which can aproach and exceed 120db per watt in some cases)

[Jet-Lee]

efficent as a bass horn (which can aproach and exceed 120db per watt in some cases)

holy shit!

[PaulD]

the term "order" came from the description of the frequency roll-off as described by a crossover. A sealed box is 1st order and has a roll-off of 6 dB/oct, a simple ported box is 2nd order and has a roll-off of 12 dB/oct. The bandpass box not only has a higher roll-off but it affects the low AND hi end - this is because both ends of the speaker are controlled. Choose the crossover points carefully .... actually, because of it's characteristics, it might make a better enclosure for a midbass since midbass speakers are bandpassed anyway thru the crossover. I would have to try it out sometime because it would also give higher volume in the bandpass to keep up with larger subs.

[Jet-Lee]

HOLY SHIT!!! You guys wouldn't believe how this thing sounds!!! This is pure tits. Building one for my buddies 12's now.