Just a little background. I currently have a Velo F1800XR (18" woofer, 250 watt rms amp, maybe 12mm of XMax). This sub is actually pretty awesome, but I am looking for a bit more output and more bass in the chest feeling.

I have been exchanging some emails with Elemental Designs and I will be having them build the subs. I am going to go with multiples of either their 18" or 15" woofer.

15" woofer link (http://www.edesignaudio.com/edv2/product_info.php?cPath=21&products_id=36)

18" woofer link (http://www.edesignaudio.com/edv2/product_info.php?cPath=21&products_id=37)

They have been very helpfull and really great to work with. However they seem to be more comfortable with large ported boxes. I am thinking of doing a smaller sealed design (maybe a ghetto version of the Submersive). I'm not worried about peak output so much as any of the options I am looking at will beat the Velodyne.

Now am I correct in thinking that I can throw a pair of drivers in a small box add lots of power and EQ and get as much extension or more then the Velodyne (rated -3db at 18hz).

Next Question.. How exactly do I do this? :confused:

Is the buttkicker amp suitable for subwoofers? That would give me 2Kw, I figure it would be a good improvement over the 250watts I have now :)

Then I would need some sort of EQ? Is the BASSIS the only thing available for that?

Now the hardest question. Are those drivers suitable for what I want to do and how much box volume would I need?

I know I sound like a moron, but this is my first foray with a non off the shelf audio product.

Thanks much.

The O series of subs are very good but you need a LOT of power and a LOT of excursion to do what you want. I'd look more at the TC Sounds subs with 30+mm of xmax. Cheating Hoffman's Iron Law costs a LOT of money.

-Robert

The O series of subs are very good but you need a LOT of power and a LOT of excursion to do what you want. I'd look more at the TC Sounds subs with 30+mm of xmax. Cheating Hoffman's Iron Law costs a LOT of money.

-Robert

Well it seems to me my Velodyne does a reasonably good job with it's 13 or so mm of Xmax and just one of the ED 15" subs should be able to equal it's displacement. I'm thinking of using four of the 15" ED subs (two woofers per enclosure, dual enclosures). That would have to be a big improvment on the Velodyne. ED is suggesting five cubic feet per box so 2.5 cu feet per driver. Could someone model that for me and see what kind of output I could get at 15 and 20hz?

I just can't imagine that I really need a bunch of 33mm XMax subs to do what I want. I mean the little SVS SB12-plus can't have much more then 20mm of xmax and it can hit 100db at 20hz (hometheaterhifi.com). I should be "way" ahead of that with what I am thinking of doing.

With two 16Ov.2s, and 2000W total, you're looking at ~106dB at 15Hz and ~111Hz at 20Hz (before room-gain, of course).

I'd build about a 6ft^3 enclosure and line the walls.

So with 2000 watts total would you reccomend dual dual 15" subs (4 16Ov.2 woofers) or a single dual 18 sub (2 19Ov.2 woofers)? It seems like it would be better for the woofers to run them with less power (less compression). But is the amplifier the limiting factor here or is it the woofers?

Thanks for the help.

2000W total would really not be enough for 4 16Ov.2's.

The amp is the limiting factor here, as far as max output is concerned. I'd say that 2 190V.2's with 2000W would be pretty good though.

There is no cheating Hoffman's Iron Law. You have low end extension, box size and efficiency. You can have any 2 at the expense of the other. So, you can shoot for the most common compromise in car audio which is either decent low end extension and small box size, but need 1000-1500 watts because of how inefficient it is, or you can play to the advantage of the car, its cabin gain and sacrifice low end extension while keeping power requirement low and keeping the box small, since cabin gain will have a sub with a F3 of say mid 50s and still play to 15Hz in car. For home it is a bit different. You can sacrifice box size and have a large box and then not need too much power and have it drop low.

You're trying to beat a Velodyne 18" with 250w right? One eD 18 and 1000w will do it even in a mid sized (4-6ft) sealed enclosure. So what are you really wanting to do, have a little more output than what you have, or blow your neighbors windows out? That being said, I doubt you need 4, 15's, but hey, it is your money. If you're going that route, you might as well buy 4, 18's, an EP2500 amp and use them IB in your ceiling. It will save you a ton of money since eD wont be building your enclosure(s).

If your doing multiple drivers and what looks to me like a decent size enclosure, why not just do an infinite baffle design? Seems to me like you might be a perfect candidate for one.

Thanks for the great help guys. I have a attic and I have thought about doing a IB with the woofers in the ceilling, but that is really quite a bit more work then I am looking for now. My main goal is to get 6-10db more output then the Velodyne while improving extension slightly (ie 15hz). I would also like dual subwoofers to hopefully help smooth the in room response and to give me some placement flexibility.

I do not need to blow out the windows here. The subwoofer will be calibrated flat (or maybe just a hair hot) and I sit 10 feet away from my main speakers which are studio monitors and rated for 115db at 1m. My room is too bright to allow listening at reference level, but I get within 3db or so comfortably.

Maybe from what I am hearing here I should go with dual sealed 18s with one driver per enclosure. What enclosure size would you recommend for a single 18? For the dual dual 15 idea, what amp would have enough power to run four of those? Do I really need 4000 watts?

Thank you

Is there a better amp for this project then the Buttkicker BKA1000-4A? The Behringer 2500 maybe, should I consider some other options? The Behringer has a fan which could be annoying so I am leaning towards the ButtKicker.

Is the Bassis the only suitable device for providing the necessary bass boost?

I am excited about this project, but I want to make sure I have a thorough understanding of all the pieces before I can commit.

thank you

The bassis isn't the only device, but probably the most simple.

You could also get a Behringer DEQ2946, or actually build your own LT circuit (but that would be the most difficult of the three).

The Buttkicker would theoretically work, but I'd actually recommend a good pro-amp for something like this. The EP2500 would be fine.

Is the buttkicker amp suitable for subwoofers? That would give me 2Kw, I figure it would be a good improvement over the 250watts I have now :)
I'm using that amp to power my deck sub. That was a "cheap" project made from ed's $25 drivers, not one geared towards critical listening, so I can't really comment too much on it, but I certainly have no complaints. I've seen other respectable posters who have reported trying it out in their systems, and could tell no difference from other respected amps they've used.

I also have to add... you won't get 2000 watts from it. If you look at the back, its listed power consumption is 1600 watts, so even if it were 100% efficient, it's not going to put out more than it takes in. If it did, the energy crisis would be over. ;) Secrets tested this amp, and found it to put out somewhere around 960w at 4 ohms. Since you list 2000w, I'm assuming you are thinking about 2ohms? It's certainly rated for that, though I'd wonder what its damping factor is at that load. It could be detrimental to transient response. Though it's hard to say without good 2ohm test data. I'd mirror Will's suggestion of something a little better geared to your needs.

Thanks for the feedback on the buttkicker amp. I would like to keep the costs down, but obviously this isn't a budget project. I am leery of Behringer because my friend has a DCX2496 digital x-over and it has gone bad three times now. He uses it in a home environment and the unit develops intermittent problems. Granted the replacements have been refurbished...

I will look at more pro amps for this and I'm not familiar with the DEQX2496 so I will look into that as well.

Thank you

edit....

I just looked at the DEQX2496 and it looks very impressive. Am I correct in thinking that I can use "Dynamic EQ" function to give me the bass boost I need and still have the other EQs to achieve a flat response at the listening position? So this device could replace the BASSIS and a EQ like the SMS-1? Can it adjust the phase of the woofers?

Having XLR ins and outs is a plus for me since I would like to run everything balanced. I am driving my studio monitors balanced from my Arcam pre-pro.

After working with my friends DCX2496 I think I can handle the UI on this. Does this come with a microphone like the Velodyne? What do you recommend for that?

One final question. Is there a non Behringer alternative to this unit for $600 or less?

Maybe from what I am hearing here I should go with dual sealed 18s with one driver per enclosure. What enclosure size would you recommend for a single 18? For the dual dual 15 idea, what amp would have enough power to run four of those? Do I really need 4000 watts?

Thank you
You really wont need 4000watts. You would be fine with a single EP2500. I'm curious why you're wanting two 18's if you're just wanting 6-10 more db's over your velodyne. A single eD 18 in an LLT enclosure with a hefty amp will accomplish what you're wanting.

Here is a picture of my gear (LLT enclosure not built yet)
eD 19Ov.2, Behringer EP2500 and Behringer DEQ2496. It's overkill, but incase one sub doesn't blow out my windows, I am equipted to power a second, third or forth in an IB design. :cool:
http://s99.photobucket.com/albums/l308/looneybomber/th_PB200313shrunk.jpg (http://i99.photobucket.com/albums/l308/looneybomber/PB200313shrunk.jpg)

You really wont need 4000watts. You would be fine with a single EP2500. I'm curious why you're wanting two 18's if you're just wanting 6-10 more db's over your velodyne. A single eD 18 in an LLT enclosure with a hefty amp will accomplish what you're wanting.

Well I would like to improve the bass extension over what I have now. I also want to stay with a sealed design so that gives up alot of efficiency to a LLT, but it is a much more manageably sized enclosure.

One of my goals for this project was to go with dual subs to get a more even response in the room. I think the sweet spot for this is two enclosures with two woofers in each unit. So I am strongly leaning towards 4 16OV.2 drivers being driven by 600 watts each. (2X1200 @2 ohms from the EP2500). If for some reason that is not enough power I can add more amp later. This way I will not have any fears about over driving the woofers, clipping the amp maybe, but I believe limiters can be set to prevent that.

Really I would probably be happy with just two of the 16OV.2 woofers, but building the second cabinet adds quite a bit of expense so it isn't that much more to throw another woofer in there. Who knows, maybe someday I will have a bigger room or second system where the extra output will be handy.

Thanks for the picture, those 19OV.2s are huge. Good luck with your project.

Loonybomber, nice gear and good luck with your project.

Megaflop, It looks like you're on the right track. 2 dual sealed boxes with two of these drivers should be able to even exceed the level of output you're looking for.

How bad are the issues in your room? I would definitely go with co-locating if the issues aren't TOO bad...reason being more output.

Megaflop, It looks like you're on the right track. 2 dual sealed boxes with two of these drivers should be able to even exceed the level of output you're looking for.

How bad are the issues in your room? I would definitely go with co-locating if the issues aren't TOO bad...reason being more output.

The issues aren't too bad. Honestly I can't really say even what they are. I have spent some time listening to my friends system and he has dual sealed 12" Titanic woofers and a transmission line DIY 18" sub. These subs are placed around the room (18 in back and 12s in the front corners). His bass sounds very rich and evenly distributed throughout the room. Mine sounds too dry and somewhat localizable. I'm hoping that splitting the bass up between two sub will give me more of the "bass from everywhere" effect that his system has. I'm looking forward to using the EQ and RTA functions on the DEQ2496 box to get everything dialed in.

I have basically decided on the DEQ2496 and the EP2500. Now I am still debating a bit about whether I should go with a single sealed 18 or dual 15s per side.

Ahh, now I see what you're after. Makes a lot of sense.

As far as amps the Carvin HD1800 is good as well. It can be had for close to the same price and is known to be a bit quieter than the Behringer EP amps.

I have basically decided on the DEQ2496 and the EP2500. Now I am still debating a bit about whether I should go with a single sealed 18 or dual 15s per side.
I would have eD give you prices on two dual 15 enclosures and two single 18 enclosures for comparison purposes. Add in the price of the drivers and see how much each route will cost you. I will promise you the four 15's will give you more bass output everywhere, but it will cost you. The question you must ask yourself, is it worth it?

Well I placed the order with eD. What started off in my mind as a smallish sealed subwoofer sort of escalated out of control. :) I originally was thinking of something about the size of a submersive. What I ended up with is a 25" cube that weighs 150lbs and holds two 16O.v2 woofers (6.3 cubic feet). Oh yeah, I have two of those coming. :D

So this is going to be a learning process for me. Next will come ordering the DEQ 2496 and EP2500.

I have a question about the DEQ2496. If I use it to implement a shelf filter to boost bass what happens below 20hz? Does the filter stop or continue on lower?

Geeze, All you guys telling me about Hoffman's Iron law are correct :o

After extensive WinISD modelling I decided the two 15s per enclosure weren't going to be fully utilized. I also measured how big a 6.3 cu foot box would be and it is quite a bit bigger then my Velodyne.

So my design has been revamped again. I am back to dual sealed 19O.v2s in a ~3.9 cu feet box (not counting bracing) that hopefully I can add stuffing to so the driver sees at least 5 cu feet. This will let me drive the woofers to xmax at 20hz with 1200 watts.

This has been quite a learning experience. Thanks for the input.

Hey MegaFlop, any updates on this thread topic?

I am interested in using a 19O.v2 (or maybe 2) in a small cube and then using a LT circuit to flatten the response out.

Judging by the displacement of the 19O.v2 and reasonable cost, it seems that that would be a good choice for this type of application.

I would like a big LLT sonotube enclosure, but I don't want something the size of a fridge in my living room.

A smallish cube LT'ed sounds like a good choice.

I am interested in using a 19O.v2 (or maybe 2) in a small cube and then using a LT circuit to flatten the response out. You may want to purchase the sub(s) before Feb 1 when the ICIX forum discount goes away. You will save $65 per sub with the discount.

-Robert