Dustin B

http://www.hometheaterforum.com/htforum/showthread.php?&postid=523602#post523602 You may find that useful. I think you are asking about what is usually called a subsonic or rumble filter. These are just a high pass filter with a corner frequency that is down very low (usually 16-25hz). These filters roll off the really deep bass protecting a driver from over excursion.

The problem is it isn't big enough for even 2 of the Dayton 15IB drivers. But for Tempests the Q is a little low unless you are using 4 or more of them. The AV15 would need even more to get the Q up out of being overdamped. Although you could always just put some bricks or something similar in the closet to reduce it's volume to be appropriate for one or two Tempest or AV15 drivers.

This won't quite be an IB, and you'll have to really beef up the closet walls for this to work and do a good job sealing it. The minimum for an IB is considered 4x the combined Vas. Your closet is 73ft^3 by your given dimensions. The Vas of a Dayton 15IB is 11ft^3. So the minimum is 88ft^3 and the recommended is 220ft^3 or more.

If you can do an IB, do it. But carefully read the FAQ on that link above and don't hesitate to ask any questions about it. Next to a well designed dipole sub an IB has no equal when it comes to sound quality. And with enough drivers they can be kings of output too. Like I said earlier, if your budget won't allow 4, do two now, but build the manifold to support 4. Then when funds permit buy 2 more drivers if the two you haven't don't put out enough bass for your tastes.

http://www.hometheaterforum.com/htforum/showthread.php?&postid=739537#post739537 http://www.hometheaterhifi.com/volume_9_3/feature-article-multiple-crossovers-9-2002.html Even K-Horns aren't what I'd call full range speakers. Very very few towers are. And even if you do have actual full range speakers I believe there are compelling reasons not to run them full range (doug pretty much covered them). The large/small naming was very unfortunate, as it plays against that guy thing of "I don't have small speakers" while the speakers physical size should not be the deciding factor for these options. For an 80hz crossover, ideally a speaker should be flat to 40hz (or flat to one octave below the crossover). Which is the real low end flat response cut off for what most people are calling full range towers. I don't know why processors have that both setting. With it the sub will receive the LFE and a lowpass of every channel. Then any channel set to large will be producing the same bass that the sub is already producing making your system more bass heavy then the recording engineer intended.

Not entirely sure. But I'd think 2 of the Dayton IB15 or Tempest drivers should be able to give an Ultra a run for its money. You have to consider that an IB is just a very large sealed sub. While the Ultra is a ported one. But best case for the Ultra would be a little over 2.5L of Vd, but the bass reflex design gives it some major help in the lowend down to its tuning point. Using 2 of each, the IB15 would be 4.8L, the Tempest 5.1L and the AV15 would be 7.4L of Vd. The Dayton has a very well suited Qts and is very cheap. The Tempest can be run RDO to get the Qts to a great value and is reasonably priced as well (buying multiple I'm sure you can get price breaks here). The AV15 can't be run RDO so the Qts is a little low. But many people are quite satisfied with an over damped IB so it might not bother you at all (but 2 of these will put you over budget). If you do some used deal hunting, you might find a suitable amp cheap that will bring a 4 driver IB into your budget.

The highpass in sub plate amps in general suck (there are a few exceptions when running line level through some more expensive subs though). So you want your receiver to take care of the bass management. With the receiver doing the crossover you don't want the lowpass on the sub cascading with the low pass the receiver is doing. So if you have a bypass switch for the crossover on the sub use it (the KSW series don't though). So the next best thing is to turn it up as high as it will go to get it out of the way.

It's an infinite baffle. The driver opperates essentially free air but you issolate the front and back waves so they can't cancel each other (two different rooms, room and attic, upstairs room to basement, basement room to upstairs, room to crawl space; just have to be two isolated spaces). To work properly you should have a space for the back side of the driver that is minimum 4x, preferrable 10x or more the combined Vas of the drivers used. The only sub that could possibly have better sound quality would be a dipole. They are also always excursion limited, not power limited. It takes very little power to push a driver to its limits when operated in free air. Also use enough drivers and very few subs could keep up output wise as well. Parts Express has a 15" driver designed for this use. $110 each when 2 or more are bought. Start with two of those and a QSC RMX850 amp ($299; although do some looking as any decent amp that will put out 100W for each driver will be more than enough). Build the manifold to support four. Then when you have the money add two more drivers and you'll be in bass heaven.

Driving under the influence? I think you meant DIY, or do it yourself. In that case easy call. Adire Audio Tempest, Adire AVA250 or Parts Express 300-794 plate amp. Then follow one of the three plans in this file: http://www.adireaudio.com/Files/VentedTempestApplications.PDF Or copy one of these: http://www.io.com/~patman/sunosub2.html http://dustin.bunnyhug.net/sonostart.php (my sub) Although if this is an option, definately do it instead: http://www.f20.parsimony.net/forum36475/ (note the FAQ and pics links at the top of the page.)

Well, without getting into details the the crossover should be set at 120hz and the phase should be set at which ever sounds better to you. Also, make sure all your speakers are set to small on your receiver and that the sub is set to yes (doesn't matter if you have towers are not, the naming of this feature on receivers is very unfortunate). If your receiver has multiple crossover options, use the lowest of 80 or 100 hertz.

yep

The subs are essentially identical (same enclosure size, same porting, same tuning, same driver, very close to same amount of power) except for a few things. Some people have problems with gain on the Sampson amps as they are ment for pro use (not many though, and a cheap radio shack component can solve the problem). The PCi has a subsonic filter that will slope off bass below the tuning point of the sub protecting the driver from bottoming. The PCi has some more connectivity options built into the plate amp (although for the most part you won't want to use them so some what of a moot point). The CS is more expensive buying one, while the PCi is more expensive buying two (Sampson amp will power 2 subs). Sampson amps do have fan noise though. So the deciding factors for me would be fan noise, and whether I might plan on adding a second sub later. Other options for the CS are to get the Parts Express 250W plate amp, or see if you can find a used proamp (our just pick up a QSC RMX850 as it's $50 cheaper than the Sampson; fan noise still an issue though).

It uses an earily version of the Siesmic 8196 18" driver. Meaningful 7hz output, highely doubt it, not enough porting and tuned too high. Chris A (HealthNut) built 4 subs using the latest iteration of that driver. Used larger ports and tuned them lower. Also spent a fraction of Wilson's asking price. http://pub66.ezboard.com/fgrouppurchaseandupcomingproductsforumfrm6.showMessage?topicID=5.topic "using a pair of 12" woofers which are quick enough to track just about any music. I wonder how those 18" woofers do tracking a tricky beat? Particularly since they don't have any servo help like the impressive Velo HGS 18." Smaller drivers aren't quicker or capable of tracking a bass line better. Cone size doesn't determine this (well to a point, but that point is well above an 18" driver), many other things determine this. Please read the below linked article and hopefully I'll eventually start making a dent at stopping this ridiculous audio myth. http://www.adireaudio.com/tech_papers/woofer_speed.htm

For one thing Sunfire doesn't make an 18" sub, 12" is the biggest they make as far as I'm aware. For another, their best 12" sub will in no way do 14hz at a decent level cleanly.

Watts are meaningless without context (context being enclosure allignment, driver senstivity and the room). So I don't know if it's impressive or not. Small cabinet with low sensitivity 12" driver and a 1000W will be anything but impressive.

It's a pair of 15" drivers. But a pair of 15" drivers in a 100L enclosure will require some serious EQ to get decent response in the last octave.

Krell, smaller enclosure and sealed. Ultra's larger enclosure and ported. Even Krell can't get around Hoffman's Iron law. Below 30hz I have no doubt that a pair of Ultra's could outgun a MRS. Abover 30hz I'm not so sure. Sound quality, well that would be up to the individual's ears as to whether the MRS is better, but I'm also quite confident few would have the expendable cash to feel comfortable saying it's $18,000 better.

The QSC850 referred to is the QSC RMX850, it is a 2ch pro audio amp. Bridged it is capable of 830W into 4ohms and sells for about $299. http://www.qscaudio.com/products/amps/rmx/rmx.htm

But they cost the same. That makes it more than fair in my books.

214L is too small for a pair of AV15 drivers. I'd want a minimum of 300L (preferrably closer to 400L) for a pair of AV15 drivers. Vd wise a pair of AV15 drivers should be capable of outgunning a single Tumult by a reasonable margin. However the Tumult does have XBL^2 which has some interesting positive sound quality attributes. If you can't find more space for the AV15, or build two seperate enclosures then I'd be inclined to say the Tumult would be a better option for you. If you can't build an appropriate enclosure for the subs they will not perform to expectations. There are always trade offs to be made. You might bet away with a good pair of 15" PRs for a single AV15. Two would then of course require four PRs. However the Stryke dual spider 18" PRs would be a better option in my opinion. For the Tumult a pair of the dual spider 18" PRs will just cut it.

Yep, folded basshorn that utilizes the same servodrive (not servo feedback) belt driven driver idea the ContraBass does. They won't win prizes for low bass output though (contrabass will though). The horn mouth isn't big enough to be very effective below 30hz or so. 25hz extension or so is possible when properly corner loaded though. 2 units have a sensitivity of 107dB/W/m and 4 have a sensitivity of 110dB/W/m. Power handling is 400W per unit. So 4 units at 10m outdoors can do 122dB cleanly from 28hz to over 100hz. Sound quality will kick *** too. Distortion will be very low, dynamic capability will be increadible. You want a sub that can cause a LaScala to miss a beat, this is it.

Enquire at http://www.rutledgeaudiodesign.com/ about a couple custom built Adire Audio Tumult based subs.

We've seen a few really bad pics. Any news on the new digital camera you were going to get Ears? We'd all really like to see some pictures of your two rooms. I'll even host the pics for you. I've got lots of space and bandwidth so for sure a bunch of nice 800*600 pictures, if not 1024*768.

http://www.hometheaterforum.com/htforum/showthread.php?&postid=944830#post944830 http://www.hometheaterforum.com/htforum/showthread.php?&postid=1196208#post1196208 I highly doubt a pair of Tumults, even in a smaller enclosure than the Krell, would lose out in 20hz output or sound quality.

Gave me a good laugh. That's all I'll say.