Drudis

It's time to upgrade my subs. I've been shopping around a bit for a budget setup of 4 12" woofers in a ported box. I want to keep my old amps, which are Kenwood 8105d's (2 of them @500 watts rms at 2ohms), so I'm looking for subs that don't need much power to perform. So far my short list is as follows:
Kenwood XW12
Pioneer Champion series
Infinity Reference 1260
Rockford Fosgate P1
Any advice on any of these? Any other suggestions?
Also I was looking at tuning specs for the Pioneers, which say that they need a port 3" diameter x 5.5" in size. What tuning frequency is that? When I plugged it in to a calculator, it said 46 hz. If they need to be tuned that high, then they're out.
Additionally, the Kenwood's need a slot port 13-3/4" x 1-1/2" x 21-1/2" in size, how can I figure out what the tuning frequency is? Also I'll probably go with circular ports as it will be easier to build the box for them.
I've been out of the game for quite a while, so any advice is greatly appreciated.

pohljm

I would advise that you dont need (4) 12"'s

abirvalg

my advice would be to weld the trunk lid shut after you're done, otherwise it might take off

and after that you may still prove that the TL seat do in fact fold down

pohljm

what trunk?

Gil'sUA5

Never heard "budget" and "(4) 12's" in the same sentence before.

abirvalg

his and everyone's driving around him

Drudis

I don't need two 12"'s either. I'm just a basshead.
Obviously trunk space isn't an issue. I haven't measured yet, but judging by the amount of extra space with my current (4.5cf) box, I shouldn't have any trouble fitting four subs at 1.75-2cf each.
It won't be as loud as you might think. I'd guess mid 140's on a termlab. Keep in mind I have 1000 watts rms to work with, and no sound deadening.
When I say budget setup, I mean I'm keeping my old amps, building my own box, and buying subs online for around $60 each. Hell that's much cheaper for four subs than my old setup of two 12" Infinity perfects.

MarcoNorthPolo

No sound deadening and it's going in the trunk of a 3 gen TL? Sign me up to see how this is going to turn out.

pohljm

(2) 15's in IB and keep your trunk

what amplifiers and speakers do you have for your front stage?

Drudis

I'm just looking to gain a few dbs. Or more than a few wouldn't hurt. I don't plan on playing it as loud as it will go regularly, just want to have the luxury of being able to show off or blast somebody out if they cut me off in traffic.
As far as the IB idea, I've never explored it. I'm certainly open to ideas, but I really just want something inexpensive that will sound good with the gains low and get loud as hell when I want it to. Trunk space isn't a big concern of mine.

Drudis

All speakers are stock (other than the subs), but that will come down the road. As will the sound deadening and front stage amps, etc. This is just the beginning of the process, and for me, I'd like to add the subs first.

pohljm

Oh my

abirvalg

have you seen this http://pwkdesigns.com/?page_id=2 ?
not a bad place to go to, if you need a great design
the fees are very reasonable

Drudis

Care to explain why this entire thread chaps your ass so bad? I don't see why a kid on the opposite end of the country putting 4 12's in his trunk is so offensive to you.

Damn, those are some impressive designs. I saved that link for the future, but for now I'll be fine building this box. I definitely dig their work though.

I hate cars

If you're looking for low 140s, a pair of the AE IB15 subs will get you there and do it lower while sounding fantastic. 1,000w won't be needed as they are very efficient. You'll have $400 total in subs, 34lbs total weight between the pair, over 90% of your trunk usable, and a very flat response that will dig to 20hz with ease and low power but also very tight and quick and accurate. These are SQ subs that get reasonably loud with little power.

That's just a suggestion. 4 ported 12s should easily outdo a pair of 15s sealed or IB in SPL but if low to mid 140s is the goal it can be reached while retaining trunk space and this is a SQ setup.

There's also the Fi IB3 15" and 18" that have 30mm one way xmax and will get loud and low but will need more power. Just another idea to retain trunk space and hit the numbers. These don't sound as good as the AE subs but they're not really supposed to.

A single 13W7 ported is capable of mid 140s and will sound great doing so. It's expensive but only one is needed.

pohljm

Not sure why thats your perception? I told you what i would do to achieve your goals. Not sure why you would not want the rest of your soundstage to be able to keep up with your subs. If your just about trying to shake the neighborhood then yes i dont agree. A balanced system would be my goal.

abirvalg

It's very affordable to just let the guy design it and give you the CAD files, that way you won't have to guess on ports sizing and frequencies tuning.
Cause i though that's what your original question was about. But by all means if you have the knowledge and the skills, go for it!
If you can, post some pictures when you're done, i'm curious to see what that beast will look like

Drudis

I'll do a little bit more research on IB setups. When I was big in the car audio game, only a select few were using them. Back then many were concerned that if the trunk wasn't sealed very well with sound deadening, then it wouldn't sound good. Just the thought of getting back the LOW lows, down in the 20hz range is worth looking into it a bit more. As for the Fi subs, thats pretty damn impressive for one sub, but having four with 13mm xmax and more cone area would be louder with less power (I'm willing to sacrifice my trunk). W7's are amazing subs, but I'm looking for budget SPL.

Maybe I jumped the gun on that, my point is that I'm only one year removed from college. I just don't have the funds to upgrade my speakers, add more speakers, add more amps, sound processing, sound deadening, upgraded electrical, etc. all at once. Hell the dealer wanted $400 to fix my stock cd player. All I have now is Isimple and the twelves and two sub amps. I plan to upgrade one piece at a time, again I just prefer to add the bass first. It'll be hard to balance out four twelves in a ported box obviously, but eventually I'll get there.

It's really not too hard to design a box. It won't be anything crazy like those designs, it'll just be a quad-chambered box with 2cf per chamber and more than likely a 4"x10" piece of PVC piping in each to tune down to 32hz.
My last box took 4 different dummy boxes (which I made out of cardboard) to get the size and angles right, because it was a 4.5cf and it fit perfectly in the hatch of my Firebird. It was a tough design, check this link for pics, and scroll down further for a pic of the box's angles. FYI it was covered in the Firebird, so it isn't carpeted/aka it looks like shit.

I hate cars

A pair of 15s will have slightly more cone area than 3 12s. When you consider the AE's 19mm xmax, a pair will displace 3.1L of air. 4 12s with 13mm xmax will displace about 2.6L of air. The Fi 15s and 18s are off the charts.

Obviously displacement is more relevant in sealed and IB applications and not quite as important in a ported setup.

If you really don't care about trunk space, try a 4th order bandpass. I had one with a pair of 12W6s and it was very musical and got stupid loud with low power and almost no cone movement. It was almost weird how loud it would be and I would shine a light into the port and the subs have maybe 1 or 2 mm of movement. Bandpass can sound very nice when designed correctly. Search for the "miracle box" is you're interested. It solved a couple problems for me with the main one being rattles. With the port coming through the skipass there was no bass in the trunk to rattle the rear shelf or trunk lid. I only got rid of that setup because I wanted my trunk space back. It actually only displaced 3 cubes total between both subs with both chambers.

The IB setup is a different animal. Where the bandpass and ported setup would get loud enough, the IB makes the car breathe on the really low stuff while actually sounding more "punchy" and "tight" but probably won't peak out as high in SPL. For what it's worth, IB has the same output potential as sealed but with less power required. The top of the windshield flexes enough that I'm waiting to break the glue or something in that area. It adds another dimension to the music something that most people don't know is there, I certainly didn't. Not all music has very low frequency content but with the capability to go below 20hz with decent output it gives a sense of energy in the air even though most if it can't be heard.

One last thing about IB, the trunk does not have to be sealed from the outside world but the cabin has to be reasonably sealed from the trunk so there's no cancellation. I've run mine by accident with the stock subwoofer hole open and there was very little difference once I sealed it so you're not going for air tight, just reasonable. Plus, there are other reasons you don't want to go airtight for your ears and sub's safety when closing doors or with airbag deployment.

But yeah, if you're looking for louder on a budget, the enclosure might be the best place to start with your current subs (have you bought them yet?). 4th order bandpass or TH are options that would only cost you time and materials and trunk space lol.

I mentioned the W7 because you can hit your SPL goal with only one instead of 4 subs.I figured the price difference would be small but that was before I looked at your potential subs at $40 each. People have had great luck with the Pyle 15s IB that also cost $40.

Last, I wouldn't trust the Pioneer's 94db sensitivity rating, especially since the units are not mentioned.

I want to specify that IB is not your best choice if you're looking for every last db, IB will get as loud as sealed but obviously ported will be louder, all else being equal. The only reason I suggested it is a pair of cheap 15s can hit low 140s on little power when installed this way.

pohljm

Cheap Pyle for me!

I hate cars

Still loving it after having it for a while now? I wish I had another car so I could try a pair.

pohljm

More than adequate for an old guy and the rap loving kids are always looking for an excuse to take my car

I hate cars

You definitely need to get a hold of me if you ever pass through this area again. I want to hear it.

Drudis

I'm looking at the Fi IB18's for an IB setup. It's between that and 4 of the Infinity Reference 12's.
The Fi's will cost more than twice that of the 12's, but I'm open to it just for the lows and punchy bass. And no I haven't bought anything yet, I want to make sure I'm making the right purchase decision.
Will the 18's even fit? How are the free air subs mounted? I know they are mounted against the back seat, but how?

I hate cars

For the money I would do a pair of IB15s. They're more suited for a trunk, especially in pairs. The Fi subs are home IB subs and especially in pairs a trunk might not have enough volume and Qtc will be pretty high. The AE subs start with a .41 Qts so by the time a pair of them are installed in a trunk Qtc is around .6. There's a guy on DIYMA that ran a pair of Fi IB3 subs in his Bently, Ill ask him his opinion.

I hate cars

For IB you'll make a baffle for the subs to mount to. Just like the front of a traditional box. It will be roughly the shape of the trunk. For the IB15s two sheets of 3/4" MDF glued together is more than enough since they're light. For the Fi subs you might need to triple up. I made one sheet with 14" cutouts for the subs to mount to and the other sheet was 15.5" so it fit snugly around the outer diameter. The baffle will go behind the seats and Be secured to the car around the outer perimeter. It should be sealed reasonably well with whatever material you want to put around the edges but it doesnt need a perfect seal. I'm the worlds worst at wood work so if I can pull it off anyone can.

I'm in the market to do another IB setup and ill make you a deal, if you don't like the IB setup I'll buy the subs from you so you won't be out any money other than for the baffle.

pohljm

18 will not fit unless the baffle is at an angle. (2) 15's is the way to go

I hate cars

True. When I was looking at doing some 18s I figured I would flip them around so the motor is facing the cabin since they would have to be at an angle to minimize loss of space.

Drudis

Gotcha, so the 18's aren't the way to go. I looked around a little for 18's (for a ported application) but my little 500w rms amps aren't enough juice for any of them.

I Hate Cars: I like your offer, I might take you up on that. Let me keep researching IB setups and I'll let you know in the next week or so. Could you share a pic of your setup? I want to get an idea of what the baffle looks like. And where are your amps mounted?
Do you not like the AE IB15's or are you just looking to upgrade?

I hate cars

I'm going to be doing one for a co worker in the future. The IB15 is a sub that does everything well. Its tight and punchy on rock and country and drops low on rap and techno. It has amazing inductance control so there's little induction induced distortion and it will play as high as you could ever want. The moving mass is lighter than most 10s. It will do anything you want it to do and it doesn't matter what kind of music you listen to.

My picture host went down, I'll have to see if I have any pictures saved on my computer. There are many people on here with IB setups, one thread has pictures of everyone's systems and in the last couple pages there are a bunch of IB setups. One person has the same subs I'm running and it looks almost identical to mine.

About a ported 18, even though the sub might be rated for a lot more than 500w, subs usually get more efficient as they get bigger. A ported 18 will probably get plenty loud off of 500w, louder than the same 10 or 12" in the same setup.

Drudis

You seem to have a wider base of knowledge on the topic, so if your sold on them, I'm convinced that I won't be disappointed with the setup. I've been extremely busy with the new job, so I still need to look into how to mount the subs. I just hope it gets loud enough, I want bass that hurts when I turn it up all the way.
I will also add that it seems like a crime to reverse mount those pretty subs (with a 30mm xmax I might add) so that you cant see the front, but after reviewing that thread mentioned (its actually linked above with pics of my current setup) there are plenty of people on here that are sold on IB setups. Any tips or links on IB baffle building? Does it just mount directly to the back seat? Thanks for all of the help.

pohljm

baffle bolted to cross braces. this is a single 15.

I hate cars

I'm worried about the output as well. I've seen these subs do 143db at something like 30hz on little power but that's still a long way off from 145db. I've never seen them pushed to their mechanical limits and metered. You could plug the numbers into a calculator, 830cm^2 cone area and 19mm xmax or 25mm xmech. Factor in cabin gain and you have a pretty good idea of what to expect. They will have crazy midbass punch. If you like that slam at 100hz, these will give incredible punch, especially important if you're running stock mids. I have no doubt you'll be happy with the sound quality but the output goal will be close.

The Fi subs would get you there for sure but they will require more than double the power for the same output. I've heard they're not as punchy or "quick" sounding but I have no first hand experience.

tegman2

iTrader: (1)

Here's mine. still not done but it will give you an idea..

I hate cars

Looks good and very familiar. One thing I learned when researching how to install mine is it's possible to get a little extra "free" output buy installing the subs as close as possible together with as little of a gap as possible between them. Just something to throw out there for anyone that might be installing a pair of subs in the future. It has something to do with mutual coupling and is the main reason you get a +3db gain when installing a second sub even when the power is cut in half to each for the same total power.

I hate cars

I thought I would throw another option out there, just ran across this in the classifieds section of DIYMA:
http://www.diymobileaudio.com/forum/...rbon-more.html

The IDQ15 is an excellent sub and works well IB. I can't remember the xmax or xmech off the top of my head though. For $100 each it's a pretty good deal.

rich20730

Looks like those are ID15's, not IDQ's

I hate cars

Damnit lol. That explains the price. I should have checked the thread out instead of getting all excited and posting the link. It doesn't seem like such a great deal now and they definitely don't have the excursion required by the OP.

Drudis

To which subs were you referring to in this statement? The same ones you have or the Fi's? I think I misread that.

Thanks everyone for the pictures, the baffles seem to be easier than building an actual box. But again I'm looking for LOUD. I'd really like to have the 20-35hz frequencies, but not if it won't be loud enough to hurt.

Any other suggestions on 15's for an IB setup that will do well with 300rms@4ohms or 500rms@2ohms (each)?

rich20730

I realize this is a stretch for your budget, but I really want someone to try these out:
http://www.woofersetc.com/p-11706-id...subwoofer.aspx

Or perhaps you could buy my IDmax 12V3's and I'll buy the 15's myself