Should I learn my ABCs or just stick with the basics?

[Harrison486 10+ year member]

Hey guys! What's going on?

Alright. Right now, my 2005 12" Kicker CompVR is in a pre-fab sealed 1.25 cf Q-logic box.

I am thinking about building a new ported box. I was thinking about this design (I dont even know if its any good or anything for a daily driver. What do you think?)



Anyway, I was doing some research, trying to figure out if this box would be any good. While doing it, I came across a box design called an ABC box. Anyone know anything about it? Here are two pictures:

It was described like: "One of the best enclosure IMO is the ABC Box. It'll make any subwoofer sound amazing. Your sub will get extremely low without loosing high end extension. If you've never tried an ABC Box, you're missing out. Believe it or not, even one crappy sub...can sound very very good...and will astonish your ears. The only drawback is the size of the enclosure. This is not an SPL enclosure...it's an SQL box.

The enclosure consists of 2 Chambers (woofer chamber & empty chamber). There are 3 ports in total...all the same length. "

Does anyone know anything about ABC boxes? Is it worth figuring out how to build one over just building a ported box? It seems like the ABC box offers the bext of both worlds, the volume of ported, and the SQ of sealed. I dont understand why more people haven't used them. (I searched and only found one person who tried to build one for a car)

So should I attempt an ABC box or is it not going to offer anything over the planned ported box?

Thanks

Click to read more...

 

[Nikuk 5,000+ posts]

they are great boxes depending on Your listening taste. they also require a bit of space. I'd definately suggest trying one. lots of output across the freq range in my experience.

-Nick

$0.02

 

[req 5,000+ posts]

id love to learn, but where to find out how is a different story - its hard enough learning how to port a box CORRECTLY, now we are getting into the realm of horns, t-lines, ABC's and all tha t good stuff.

 

[Nikuk 5,000+ posts]

ABC's are ****ing cake. there is a 15ish page long thread at termpro that'll teach You, if You if You cant figure it out.

-nick

 

[req 5,000+ posts]

care to link? im up for a good read.

 

[the_noob 10+ year member]

care to link? im up for a good read.

I found a bunch of links, but they were all dead. However, I did find this.

Ok, here it comes one time! I only explain these in detail once a year (I make $$ on them )For that DVC 15. Build a box with 2 chambers, one at 3 cuft and the other one EXACTLY half of that, ie 1.5 cuft. Next cut 3 ports all IDENTICAL in length. Put one in the face of each chamber and the third in the wall separating the two chambers. In this instance each port would be either 12.5" long for a little deeper response or 8" long for a little more SPL.

Now you have a box with a big chamber with a vent in it, a small chamber with a vent in it, and a third vent in the wall between the two. The woofer also mounts in the large chamber.

The way they work is that, at low frequencies, it all functions as one big box with 2 ports, and is tuned to 30Hz (12.5") or 35HZ (8"). At higher frequencies the middle port starts to restrict air movement and the second chamber begins to act more as a resonance chamber but not as part of the box. At this point a second tuning frequency develops 1.9 times (almost an octave) higher than the lower one , ie. either at 57Hz (12.5") or 67Hz (8").

This is similar to a vented bandpass but has more output and smoother sound due to the woofer not being tucked inside the box. The results are that it plays both low and loud, while being relatively nice sounding. The drawback is the box size.

Did one 2 years ago in a sedan with 1 12 on 400 watts and pulled a 138 on music. There's a guy around here with 2 DVC 15s like this in a Daytona off a single 800a2 pulling 149s.

They work but can be intense to build. They are the ONLY box I take care to factor exactly both port displacement and woofer displacement. Mess one of these up and they work very poorly....

Looks simple...

 

[Harrison486 10+ year member]

First, let me explain my musical tastes and how much room I have

I listen to almost exclusively rap and hip-hop.

The max dimensions of my box can only be 14" high, 36" wide, and 36" deep, although that would be my entire trunk

What do you think I should do?

What that ported box I posted above be fine?

Or does an ABC box really outperform a ported box?

 

[Nikuk 5,000+ posts]

exactly.

yes it really does tune by the octave.

yes it really does unload the middle port at certain ranges.

yes it really works as a bi-tuned ported.

That is from TP, a la` "Dukk" iirc.

Git er done...

 

[Nikuk 5,000+ posts]

for mainly rap & hip-hop... just go big ported low tune.

$0.02

 

[bumpin_blazer 5,000+ posts]

ABC's to me are a waste of time and space due to their size with real lack of SPL gain. I've built one for my SI D2 12" when I had it. Tried that sub in sealed, ported, ABC, and 4th order bandpass. The ported wasn't as loud as bandpass but louder than ABC and 1/2 the size. ABC's give a great response at many different frequencies where as ported give's you a nice kick at a certain 5-10hz or so. How I usually just guess it at is like this, a ported box has a theoretical 5db's over sealed, so I just would say that an ABC enclosure has about 3db's on sealed, well in my experience that is.

 

[the_noob 10+ year member]

ABC's to me are a waste of time and space due to their size with real lack of SPL gain. I've built one for my SI D2 12" when I had it. Tried that sub in sealed, ported, ABC, and 4th order bandpass. The ported wasn't as loud as bandpass but louder than ABC and 1/2 the size. ABC's give a great response at many different frequencies where as ported give's you a nice kick at a certain 5-10hz or so. How I usually just guess it at is like this, a ported box has a theoretical 5db's over sealed, so I just would say that an ABC enclosure has about 3db's on sealed, well in my experience that is.

But did you lose any SQ going ported?

I don't believe that ABC boxes are really meant to be louder than ported, just kind of like a loud SQ box (at least from what I've read so far), right?

 

[bumpin_blazer 5,000+ posts]

But did you lose any SQ going ported?
I don't believe that ABC boxes are really meant to be louder than ported, just kind of like a loud SQ box (at least from what I've read so far), right?

Sq is relative so that's a hard question to answer. Then again, I did tune the ported box to 32hz so that keeps it IMO sounding as good as sealed from 26-40hz.

 

[req 5,000+ posts]

ABC's are ****ing cake. there is a 15ish page long thread at termpro that'll teach You, if You if You cant figure it out.
-nick

so care to post a link for the commonwealth?? //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

 

[bumpin_blazer 5,000+ posts]

so care to post a link for the commonwealth?? //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

ABC's truely are simple. As stated say your sub needs a 3cuft ported box. Make yourself a box that is a total of 4.5cuft with a board that cuts the box into 2 chambers of 3cuft where the sub will be mounted, and 1.5cuft where the other port will go. You then take 3 pvc pipes cut and made to your desired tuning length and drop em' in da box. The tubing is the hard part but even then if you're good at ported box's it isn't hard.

 

[req 5,000+ posts]

wait wait.

so i would do the port length depending on a SINGLE 3" port (say winISD) or 3 3" ports?

because how the hell do you get the length //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

i understand the 1:1\2 box size ratio. i under stand how it works and how to build them. but how do you measure the tuning versus port length on these - since there are 3 ports.