My ABC towers.

[Duke 0]

I finally got them BOTH done and hooked up. I'm not putting a finish on them. They look fine to me. They're made out of 3/4" MDF with oak laminated onto them. On the edges you can see the MDF, but at this point, not a big deal to me. These needed to stay rather cheap so I didn't buy very nice wood. Each tower houses 2 Dayton DC160s (8ohm versions), one HiVi TN28 (6 ohms) and an 8 ohm 3khz passive crossover(from Partsexpress). Both towers are powered by a Dayton APA150 in stereo mode, running at just under 4 ohms. The source of audio is my computer. These things sound awesome. They respond very audibly into the low 40s, and audibly into the 30s. The best word I can think of to describe the sound is "Thunderous!". I still need to tweak the EQ on the computer, but I can't imagine them sounding much better than they already do. Some pics are slightly blurry as my hands are gargantuan, unsteady and I didn't feel like hunting down teh tripod. Yeah, I know... my room sucks too.

Countersunk terminals.

[Adrian_D 520]

I like the way they look

Would preffer a bit wider baffle for added stregth.

[seanbw 1]

very cool, looks like it was a fun build.

[topgun 262]

Looks like pretty decent construction. Who designed them? The one thing that stick out that I would do different is on your side/back panels I would have ran the wood grain vertical rather than horizontal.

[KU40 173]

looks nice. But does that crossover do 4 ohms for the mid output? Otherwise your crossover for the mids is either at 1.5khz or 6khz (I forgot if halving the impedence halves the crossover or doubles it). Your tweeter crossover point is also not going to be 3khz. I hope it sounds ok in the midrange.

[Aaron Clinton 2,372]

Looks good. Only makes me want to start my project sooner.

[Duke 0]

Ehh, the cabinet is plenty strong and was built just like alot of enclosures are... I don't see why more strength would be needed. Definitely a fun build and worth it. I wanted to run the wood grain vertical... but the precut 4x4 sheets I bought were one inch too short that way. The crossover... I don't know. Its just listed on Partsexpress as an 8ohm crossover... maybe meant to be used with an 8 ohm tweeter... no idea, not a big deal to me since it does its job. I do know however that there is no vocal/midrange problems at all. I'll be doing a graph hopefully tomorrow of these things at my listening position. The speakers are all wired parallel, but the mids are not crossed over. They're getting a full signal. I can crank these things as loud as the amp can get them and they still sound just, immaculate.

Denim, what project do you have that you're wanting to start?

[B7L|BL4Z3R 4]

i def dont understand that chit, its so like confusing at least it looks that way to me

[Duke 0]

i def dont understand that chit, its so like confusing at least it looks that way to me

Well, ABC stands for Aperiodic Bi Chamber. The speakers's rear wave fires into a chamber which port itself into two areas: The upper port fires directly into the room surrounding the speaker. The other port goes to a second chamber which also has a tuning frequency, then fires out to the environment also. The box achieves two tuning frequencies, giving it a nice long frequency response. Some compare it to a 6th order bandpass box which also has two tuning frequencies. These are much easier to design and usually sound better from what I've read, due to the fact that the woofer isn't fully enclosed.

The second chamber acts sort of like a filter and a small room It takes the sound in the "small room"(second chamber) and EQs it a bit to sound different, then, what you hear in the actual room is the result. I think I'm right on track here, anyone feel free to chime in.

Edited December 31, 2008 by Duke

[Duke 0]

Here we go. I haven't done any EQing. First one is without me in the seat, second one is with me in the seat. Not really that big of a difference... *WPSHHHH!* The lowest DB reading is -55 at 20 hz, and the highest is +1db at around 4 khz.

I did tons of testing with the mic in different positions and there weren't a whole lot of variances. These are with the mic pointing almost horizontal at the monitor(which is in the middle of the towers roughly 3 1/2 feet from each tower.). The towers are angled towards my seat.

[B7L|BL4Z3R 4]

do you think if i made a new box for my house 15 then what i bought it in it would be louder

[Duke 0]

do you think if i made a new box for my house 15 then what i bought it in it would be louder

Possibly. You could just build a random cubic foot box tuned to a low frequency and see what happens... or you could read up on placement, mass ratios, wavelengths, etc. There are alot of variables that go into a box and how it will do in a room. If you were to build a low tuned box, you could probably get away with it, and just use a good bass eq to fine tune it as much as you can.

[Duke 0]

After some tweaking.

[Duke 0]

If you've never used True RTA before, each darker horizontal line represents 5 db, while each lighter colored line represents 1 db. The biggest variance in most of the range is 2 dbs, until you get to 9 khz where you can see it drops off hard. For the lower, it drops off hard around 29. I get to see how this "flat" sounds with music today after a few more tweaks.

[Aaron Clinton 2,372]

Some of the pictures links are broken. As for me, I would like to do a small bookshelf set for a decent price. Then build a pair of towers and a sub enclosure for out main stereo.

[topgun 262]

Some of the pictures links are broken. As for me, I would like to do a small bookshelf set for a decent price. Then build a pair of towers and a sub enclosure for out main stereo.

I think you need a set of the Fonkens from planet10-hifi.com... I might even know a guy who does woodworking that enjoys building such things too.

[Duke 0]

Some of the pictures links are broken. As for me, I would like to do a small bookshelf set for a decent price. Then build a pair of towers and a sub enclosure for out main stereo.

Which ones are broken? They're all loading up for me.

[NB50 206]

Post #10.

[Duke 0]

I have failed at finding the edit button, so here is what those were. These were unEQed responses at the head of my chair... no sealed up on the desk.

[topgun 262]

Holy 20dB jump at 5k batman!

[Duke 0]

Holy 20dB jump at 5k batman!

Yeah lawl. For just hooking up everything without tweaking the EQ(which was set to "flat") it didn't even sound bad... I think I posted it earlier, but this is what it resembles now.

Going to be doing more tests/tweaks as soon as people aren't sleeping and I'm not at work.