Simi's Official 12" subwoofer build.

[similost]

Well, I got one speakers box built and it's in the house thumping away.. sort of... I don't have enough amp for it..

So first, the PF-MOD box I got.. MAN is that thing cool. Right now I have it set to cross over at 52hz. It seems to be what playes the nicest with my speakers. It doesn't seem to sound off at all. I had started out crossed at 120hz, then dropped to 85, and not to 52.. and 52hz sound by far the best. I might try a little lower. The crossover works very nice though, so for those needing a way to get a crossover in your system for a sub, I don't think you can go wrong with this. .

I haven't run any test tones through it or similar yet. As I said, my amp, a crown D150, just doesn't have enough ass to really run it. It doesn't take much to put the amp into clipping.

I can say though, I sure have found what I've been missing watching TV with it all last night. I did try some music too, but again, not enough amp..

The one thing that bummed me, was I couldn't find 1" board of any kind in my area, so I went with 3/4". After I got the box together, and knock on it, it sounds nice and solid. Not any right to it, other than on the far port wall.. on the outside.. The sound from this is very solid, and amazingly low. I can't wait to run some tones through it and see what it will really do, but I will say my window seem to be kinda loose..

So here's some pictures.

 

[similost]

Oh, I gluded and screwed the whole box, and it's by far the most solid box I've ever had speakers in.. After I get the second one done I'll start with the veneer..

 

[dumptruck]

Lookin' good. I was gonna say you went a little light with the bracing - coulda put a truss or two front-to-back, supported the slot in a couple places, etc. Then I saw that they will be on the broad side with a big speaker on top. That should do it.

Still might want to check the actual port tuning before going to veneer. It's a little bit of a pain without a woofer tester, but pain is relative right?

 

[similost]

sooooo.. .how would I test the tuning? Don't tell me with mics and meters, cause that ain't gonna happen.. .

Sound wise, sure sounds good.. I don't know about being able to over excurse them or not, because I ain't got enough amp available to really push them.. Still waiting to bet the Ashly..

I had thought about the front to back bracing... OH WELL.. too late now.. that box is sealed..

 

[dumptruck]

You'd need a multimeter, not a mic. If you search around for "verify port tuning electrically" or something like that, you'll see.

 

[similost]

I found a bit about it... what a pain in the ass... and if it's not right, then all I can do is build a new box.. and I really don't wanna fund that again..

So what if the tuning is off? What problems can that create?

 

[dumptruck]

So what if the tuning is off? What problems can that create?

Well, with this driver on a sub crossover, not that much of any problem, in a way. You've got a pretty wide range of useable tunings. Way too low, you lose some power handling below 30Hz, but it still basically works fine, way too high and you start losing output really fast below 40Hz (noticeable by ear) and again power handling below 30Hz.

You wouldn't necessarily have to build a new box - there are a bunch of things you could do through the woofer hole to adjust the tuning.

 

[similost]

hhhmm... ok..

Well I will say, with what I could get out of it from the weak amp I had on it.. holy crap.. these things are gonna shake my house apart... it was pretty amazing what I could feel and not hear..

I don't know how close the tuning is, but I can say it sure seemed to do what it was uspposed to do.. I just couldn't get enought power into it without clipping my amp.

Hopefully tonight I can run some test tones through it, even with this amp, and get an idea of how well it's working..

 

[Guest158]

Did you pick up a CX-3400? You may want to try it before another amp.I used some of the Harrison fmod 70hz xovers on my QSC CX-502 amp.Seemed to attenuate the signal-amp should have been able to push the 400 max to my Lab 12s but struggled.Now have a Cx-3400- nice to have another gain-they get full power now.

 

[similost]

yep.. I got it, but i can't use it until I make up a handful of cables and get the amp I'll be using for the subs. The little PF-MOD I got seems to do a really great job, it was just finding a crossover point that didn't make it sound strange.. now all I got is good heavy thump. At 120hz, it sounded like there was a huge lump in the sound. When I went to 85 hz it wasn't so bad, so that's why I dropped to 52hz... I know the drivers in my barzi's do a good job until around 40hz or so. Then unless I push a lot of volume, they don't like to hit hard. With a lot of volume, they tend to do well until around 35hz.

Interesting you say you found the fmod seemed to attenuate the signal. I kinda think that's what's happening with me too... I removed it and fel full range to the sub, and it seemed to be louder for sure.. but I couldn't tell if that was because of higher freqs, or because it was getting more power.

 

[Guest158]

I have my labs crossed at 60hz(prob about as low as the Kustom cabs go) & made some changes yesterday.Put legs on the Cubo cabs & pointed mouth to floor.Moved them to either end of the couch.They only chart the Cubo cabs from 44hz-up but man with the labs in there its a fun couch ride! Can feel vibes in your feet on the concrete as well.They blend better than they ever have-took the boxy sound out they tended to have.Still looking at horn designs that will go lower but the size of cabs really goes up.
I think you will be happy with the Labs!

 

[similost]

FOr just a short listen last night, and not really being able to push them very loud, I was WAY more than happy finding out what I was missing. Even at low volumes, it was amazing the amount of shaking I was feeling, much less hearing..

If it wasn't so much work I'd pull out a bigger amp, but it took me an hour to put it back in place the last time I pulled it from my large system... Gonna have to wait until I can get this other one to really find out what this single sub is capable of. Will probably get the second one built next weekend.

 

[x_25]

I basicly run 3 10" subs in my system (well, two now since the one driver is down for repair), the mains have 10" subs then a 10" jbl that I picked up, while it doesn't do much that little jbl sub sure makes a difference. :yes: sometime down the line I want to try a swarm of subs, may look into one or two 12's like you are building then a pair of 8's arround the room.

 

[similost]

Well OK... I just got done running some test tones through this sub, and DAMN... although I had to keep the volume just below clipping, it was still pretty amazing..

First off, I'm not sold on this Fmod.. I ran up to 200hz and that tone was passing into the sub like it wasn't even filtered. around 300hz it started rolling off pretty hard, but also pulling the mod and trying the tones, yep, more volume, so it is attenuating the volume levels more than I care for while not filtering as much as I'd expect it to. Time to get busy with cables.

So... I'm not hearing any problems with volume levels at 30hz and below. It was really wild seeing and feeling how much air was blasting outta the port at 20hz, and hot damn, no port noise...

Granted, without really checking the tuning right with the meter like I read about, I can't be sure, but it sure does seem to perform well with all the tones I was running, and none really seemed any louder or quieter than the next.

I wish I did know someone near me though that really knows how to test them, and has built some subs just to get their opinions about the sound and measurements... I'm just not very versed in subs like this.... nor testing any speakers.. I just go by ear. I know I like what I'm hearing.. :thmbsp:

 

[Jailtime]

Nice boxes, James. I wish I could build something like that. I bet there's a whole lotta shakin' goin on in Kato's cage.

 

[similost]

I used a sheet and a half, and I sill had to use cheaper ply I had laying around for the brace in the center.

I agree, in foresight I should have used one more brace, but DAMN are these boxes solid, Don't ring when I knock on them, and even more impressive to myself, I got them air tight.. and... SQUARE..

That was a feat I didn't know I could perform. First larger boxes I've ever built.

I just can't wait to get the right crossover and amp on them.

 

[djnagle]

Good job Sim.

 

[Altec Best]

Yup Simi Lookin good.I just love these DIY projects aren't they awesome ? You got to love when a plan comes together !

 

[similost]

I got the second one done yesterday. With the amp I have them on, I'm not finding out the true potential, but I will say it's pretty amazing when there's a movine on that ues a lot of super low bass. I've also found it real interesting what music has that really deep low bass, and what doesn't...

After I get the other amp I'm waiting on, and get this hooked up using the Behringer, then I'll have to let you know how successful I was. From what I can tell, I've got some really nice sounding subs, but without being able to put much power into them, I really can't get an idea of how well they will perform.

 

[Jailtime]

Break out the Tapco!