maltesechicken

I think I understand how to build an ABC correctly:

A normal box - 3 cubic feet, tuned to 32 hz with two 3" ports (round): each port is 9.96" long
To make this ABC:
Woofer chamber 2 cubic feet, one 3" x 9.96" port to exterior.
Second chamber 1 cubic foot, one 3" x 9.96" port to exterior.
One 3" x 9.96" port joining the chambers.

Is this correct?
Also, anyone with lots of experience on this (Dukk perhaps) - is this a good size box, or should I reconsider. Here is the Sub:
Clif Designs CD10W
Qes:0.63
Qms:5.39
Qts:0.55
Vas:30.8L
Fs:34hz
Re:3.2
xmax:31mm (this number seems high - I'm wondering 15.5mm one way?)
300 WRMS

Thanks,
Ryan

efxtruck

That XMAX dose seem a little much I would email the company and ask them.

Dukk

You got it right. I like to take vent and driver displacements into account, but that's just a tweak.

Is that a 10? You want to use one 10? At 3cuft, I would think 2 is a better idea. I don't have software here to run but you have to make sure the woofer isn't going to freak out from being in too big a box.

BigRedGuy

iTrader: (11)

Here we go again.......

I swear there will be an ABC box stalking you into your grave.......

maltesechicken

Yeah its a single 10"
I played with it on WinISD and it's a sub that is more recommended for sealed. If I bring it down to 2.5 cubes, it still has a good response curve, but as I approach 2 cubes, it starts to roll off too soon.

. . . also, my plan for later on is to convert the same box from ABC, to a dual ported tuned to 32hz (so each sub has 1.5 cubes). - Basically, I would cut out the interior baffle wall, or make it removable when I build it.

. . . so that's why I'm thinkin' 3 cubes - but I am willing listen to suggestions from anyone who'll through those numbers through a program and give me other suggestions.

Thanks,
Ryan

maltesechicken

Here are the Graphs:
Green = 3 cubes tuned to 32hz
Blue = 2 cubes tuned to 32 hz
Yellow = 1.5 cubes tuned to 34hz


I suppose that the curves aren't THAT bad, but I don't really like it when a box begins to roll off before 40hz . . . I love my low rumbles powerful and strong, so if a box can peak around 35 hz, I'll be happier than a pig in . . . .

But I suppose there comes a danger of mechanically messing up a woofer up as a consequence of my thirst for deep bass.

One other thing - its rated for 300wrms. I'll be running it off an amp capable of 500wrms into a 4 ohm load. I know the bigger the box the less power it should be given, so what are some good recommendations based on my preferences:

I want it ported
I want it low
And I want to give it as much power as possible

(I only paid $20 for it, so if I do screw it up, no real loss)

jalat

iTrader: (6)

becare ful the gains, because ABC boxes are like t-lines, you shouldnt run more than rms power to the woofer.

maltesechicken

t-lines?
I'm unfamiliar with this terminology.
I'll likely keep the gains at 1/4 at the most (my deck only has 2v pre-outs) so I'm hoping that 1/4 with 2v won't be more than 300wrms

I won't be building for at least a few weeks, so all helpful information before I set to the wood will be appreciated . . . I suppose the first order of business is deciding if I go with the 2 cubic feet or 1.5 as it appears my 3 cubic feet is just too dangerous.

John__Taylor

iTrader: (3)

Killer_Klown187 has investigated those enclosres and built quite a few...

I was reading the entire board one night () and came across a small thread. It's a fairly complex box that may take some trial and error.

maltesechicken

I found this quote on another web-page
"The primary advantage of the dual-chamber system over a simple ported system using the same driver is a further reduction in driver excursion, caused by the addition of a second port resonance within the passband of the system. This reduction in excursion results in increased power handling within the system's passband, making this type of system particularly suitable for use for drivers with low Xmax."

Is that accurate? Increases power handling seems counter intuitive . . . if it can increase power handling & output at the same time it would be a miracle box . . . any thoughts?

Also, on the same page this was noted:
"Almost any driver can be used in a ported enclosure system, however, only drivers which have a Qts value between 0.2 to 0.5 will generally give satisfactory results. If the driver has a Qts above 0.4, try using it in a sealed enclosure or single reflex bandpass system instead."

Since the QTS of this woofer is 0.55, I should probably save this project for an other sub (or pair of subs)