Dustin B

The DPL12 will be destroyed if feed 600W in that allignment. Mechanical travel limits and thermal power handling limits are two different things. Depending on the allignment it can take very little power to reach the mechanical travel limits of the driver. Thermal power handling is just how much power the voice coils can take before they start to melt, not how much power the driver should recieve.

SVS would be my commercial vote. http://www.acoustic-visions.com/ or rutledge/"]http://www.rutledgeaudiodesign.com would be my custom built vote (these guys should be able to match or beat anything SVS offers for the same or less money). But if you want the ultimate in loud low bass (well the ultimate would be a massive basshorn, but the mouth required for 15hz extension will make it impractical) you need to build an infinite baffle: http://www.f20.parsimony.net/forum36475/ Say 6 Stryke AV15 drivers in a nice manifold with mid 100W power per driver. Total cost including a good pro amp should be under $2k.

Fs is the resonant frequency of the driver. A driver can play below it's Fs. The Tumult was designed with the intension of being used in a smallish sealed enclosure and then EQed flat to below 20hz (peferrably with a Linkwitz Transform circuit). The current tech of foam surround is very different from a while ago. Treated foam will last as long as rubber. Foam also has a more consistent compliance making it a better surround material than rubber (now that it will last just as long). There is a reason all of Adire's sub drivers use foam surrounds. As Firepinch said, get WinISD pro or some other modelling software (Unibox is another good free one). Learn the basics of using them and model away.

Here are some links to Adire's reference designs for both the Shiva and Tempest. http://www.adireaudio.com/tech_papers/shiva_apps.htm http://www.adireaudio.com/tech_papers/tempest_apps.htm If you can DIY the extra $25 on the Tempest is a no brainer provided you are ok with the much larger enclosure requirements. In both cases the preferred price/performance amp choice is the Parts Express 300-794 or the Adire AVA250. In proper enclosures both of these drivers can be pushed to their limits with only 250W. You may also want to look at the Stryke AV12 or AV15. As for the Dharman, right on par with the SVS CS or PCi series IMO. Also don't forget SVS now has the PB1 ISD which is essentially a 25-31PCi tuned to 22hz and a box instead of a tube.

Save DIY (or something from Acoustic Visions or Rutledge Audio at very close to the same price), nothing for less money. In fact there isn't a lot out there ignoring price.

Ear, you're forgetting about the allignment. The Ultra is a bass reflex allignment tuned to 20hz. The MRS is sealed. Doesn't matter how great you think the MRS amp is, a watt is a watt when it comes to spl at 20hz (and I really doubt you could tell the difference between a Crown K2 or the Krell amp powering an MRS). I'd believe the MRS could do 120dB at 20hz in a small concrete bunker measured at less than a meter, going by what a Tumult models as capable of anyways.

I'd really like to see the Krell MRS hit 120dB at 20hz with less than 10%THD in a 2500-3000ft^3 room with the sub 12-16ft from the listening position. Simply put, it won't happen. Infact I really doubt it could do that much more than a pair of Ultras could at 20hz.

Formaica's Prosound Web LAB12 Basshorn project suggestion is exactly what you are looking for. The enclosure was designed by Tom Danley and Eminence worked in conjunction with him to offer a driver specifically designed for this project. Just so happens it's $150US and you'll need two of them. It's available at Parts Express. http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=290-570

I know it's hard, but you have to get past looks. There are many car audio drivers that look even more impressive than the Tumult or TV12, but when it comes right down to it they aren't even a 1/4 the driver either of those is. Can't really do a B4 or B2 style sub with a Tumult. It was designed for a different purpose (small sealed, although IB and passive radiator will work as well). You'd underdamp it in an enclosure large enough to house sufficient porting for the air a Tumult can displace (which my guess is almost twice what a TV12 can).

No arguement there, I'd take a B2 or a B4 over an Aerial anyday. Infact if it didn't cost more than twice as much I'd consider a B2 over my Tempest.

But don't forget both require frieght shipping. So shipping on a pair of B2 subs will be more than a single B4.

The issue will be the B4+ is already underported. Switch to TV12 drivers and you just compound the problem. In otherwords there would be no benefit to using TV12 drivers over the DB12 driver in the B4+ as the DB12 driver can't reach their full potential with the current porting. However, since what it can reach with the current porting is more than most people will every use TV didn't really care that it was underported.

2000W would be way way overkill for 4 AV15 subs. Less than a 1000W would allow you to bottom them. 4 Tumults couldn't even take 2000W in an IB configuration.

Adire, Stryke and Parts Express all have drivers that would work really well for IB use. In a balanced manifold arrangement the drivers cancel all mechanical forces on the wall. But if the amount of air being moved causes the walls to vibrate won't matter if it's an IB or a box sub in the room. So really in my opinion that concern of yours is a moot point. If money isn't an issue load up on Tumults, they'll kick the crap out of an equivalent number of TV12 drivers. If money is only sort of a problem go with Stryke AV15 drivers. Use enough to get over 20L of Vd and in a moderately sized room you'll have sick levels of bass with a quality level that will put any of the subs you claim to own in second place. If money is a big concern $400 will get you 4 of the PE 15IB drivers. And there aren't many commercial subs at any price that could compete with the output and sound quality of that setup, so you kind of get the idea of what the AV15 or Tumult IB subs could do. The only real concern you could have is to make sure (that is if you actually do this which for some reason I just don't think you actually will) that space you speak of is large enough. The rule of thumb is a minimum of 4x the combined Vas of the drivers being used. This is not ideal however, preferrably you want 10x or more the combined Vas of the drivers.

The PW2200 is tuned to just under 30hz, the SVS PB1 is tuned to 22hz. The SVS will outgun, and out extend it. The PW2200 makes sense for Canadians who can get it for significantly less than they can get a PB1. But if the price is close, the SVS is the clear choice in my books. PS1200 and PW2200 are very different subs. The PS1200 is bandpass junk and the PW2200 is a good sub.

http://www.royaldevice.com/custom3.htm I believe this is what you are talking about. Didn't use his basement, just built the room with a 1m space below to house the two giant horn mouths. Also didn't use wire and stucco, that's brick and other assorted masonry. Don't think I'll every do something like that, but I won't say every. But there is a significantly higher probability I'll do an infinite baffle. http://www.f20.parsimony.net/forum36475/ and in case you miss it on that page, here's the link to pictures of many different IB installs http://t-3.cc/users/audioworx/page100IB-Gallery.html

I like how Jack Gilvey puts it. Here are two quotes from him: 1) As long as flat, extended deep bass doesn't strike you as amusical, then the SVS's are "musical". Many audiophiles find the presence of deep bass anathema, and much prefer subs which roll off deep bass giving the impression of "tightness" while, in actuality, it's "leanness". I find accurate reproduction of as wide a bandwidth as possible very "musical" as long as it's not at the expense of smooth FR or good transient response, a price not paid with an SVS or other well-engineered reflex designs. 2) I love hardware forum discussions on subwoofers...makes you really appreciate the DIY area. All kinds of "puffery" without the need for any knowledge apart from "I think it has more output" or "I think it's more musical". Output claims from uncontrolled listening sessions are invalid and ridiculous. "Musical" means whatever someone wants it to mean, although it's usually associated with rolled-off deep bass, a "low-Q" shape to the FR curve.

Ray, if folded bass horns rule so much, at least get some decent ones instead of trolling. http://www.servodrive.com/bt7.html or build 2 or 4 of these http://www.prosoundweb.com/lsp/ It's a free design done by the guy who designed the BassTech7 and came up with the summation apperature in ServoDrive's speakers (the summation apperature was also made available in kit form with the Lambda Unity Horn kit).

I don't think it has any real effect on the sound. It has more of an effect on the amount of power it takes ot get a driver to a certain excursion level and therefore also the spl level. Admittedly, this and horns are the the bass topics I understand the least and I'm partly talking out of my *** here.

With sufficient distance between the driver and base plate, it will have no effect on the sub's sound. However, as you get the plate closer to the driver, there isn't enough space for the air to flow freely and you end up doing something called loading the driver (the air can't escape fast enough and causes some back pressure on the driver; at least I think this is what loading is). The SVSubs may do this, I'm not sure if the little over 2" of clearance is enough to not have any loading effects. But if there are loading effects you can be sure TomV designed for them. Unless you have good measurement equipment and know the drivers parameters I wouldn't attempt to load a commercial subs driver. Some people seem to think that carpet will absorb bass energy. Yes it could, if the underlay was 3 feet thick. Typical carpet and underlay is transparent to bass frequencies.

I'll say it, definately small. Rather than rehash it here Brian Florian did an excellent job explaining what is going on over at AVS. Here is a link to where I quoted it in another thread on HTF: http://www.hometheaterforum.com/htforum/showthread.php?&postid=739537#post739537 And from that one, this article at Secrets of HiFi was born: http://www.hometheaterhifi.com/volume_9_3/feature-article-multiple-crossovers-9-2002.html

Out of those companies, besides the SVS B4+ (but for it's cost you could build a sub with multiple AV15 drivers that will match or beat it), I'd bet money only the soon to be released B2+ will be able to compete with a properly built vented AV15. The shoot outs have been done on other forums and it ends up being pretty consistent. DIY results in the most sub for the money, for the most part by a very large margin. The only time commercial subs can close the gap is if size is also a major consideration (but even then DIY will still be cheaper, just not as much).

Frankie's right, SVS doesn't sell stand alone drivers. Just replacement parts for damaged SVSubs. Getting the horn right isn't a trivial exercise. But you're in luck since Tom Danley and Eminence were kind enough to design a bass horn for DIYers. http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=290-570&DID=7 There are links to the forum and to enclosure drawings on that PE page. Not an easy enclosure to build, but it will definately meet your performance goals with ease.

Um, without plugging a port the B4 is tuned to 25hz. It won't be a bottom dweller in this config, but it will be capable of one hell of a punch.

Um, how will a driver with a 0.5L displacement ability go louder than the Shiva, Dayton DVC12 or the Inifinity 12" mentioned which all have a 1.5L displacement ability? Oh, and by the way, Emminence is the manufacturer who produces Adire's designs.