DS-21

Just the 12's? Not that it isn't a killer woofer, and IMO the best 12" woofer on the market right now. But I'm already using two for the "broadband" subs in my main home systems, with an NS15 anchoring the system. If you could offer the NS18 for the same discount, I'd be in. The nearfield home system could use some Aura NRT-ing, though the Maelstrom-X in there now is certainly no slouch.

Except for the RLi-8, which should be an excellent driver (based on my experience with the 15" TC2+ that O-Audio used to carry), all of the drivers mentioned so far are not really up for high-fidelity audio use. If you're looking for something better, try the CSS Trio8. XBL^2 motor with multiple shorting rings, long throw, well-made, and 80 USD a pop. If that's too pricey, look at the Peerless SLS8. Excellent motor with shorting ring, good suspension, basket is stamped but well-designed with under-spider ventilation. VERY solid driver for in-car use.

The simple reason is that most "high end" reviewers are deaf. They couldn't tell you two things sounded the same if one of them was an empty box that turned the other one on! The real answer is that some of them are potentially worth the money. Lexicon, Meridian, and TacT have seriously advanced room correction, processing that may make the system sound better than other stuff. Anthem also has some sophisticated room correction horsepower. The rest of them are very expensive, and soon to be very obsolete with no resale value to mention. (I recently saw an Angstrom Pro-Logic preamp. It was beautifully built, and cost tons when it came out. It was selling for 200 USD.) For my money, however, I'm going to stick with a "mass marketer" that uses well-engineered room correction system. My preference is Audyssey MultEQ XT, which today means Denon, Onkyo, or NAD. My Denon AVR-4308 receiver, with Audyssey MultEQ XT and Dynamic EQ, will sound better than five figures of Krell, McIntosh, or Levinson with the same speaker installation.

Thanks, Scott. I haven't decided if I want to use the gasket or simply put the frame on weatherstripping. The matte aluminum basket might look really nice against one of the enclosure finishes I'm contemplating. And the Ava18 should be on its way to you from Florida now.

I am indeed talking about the old XBL^2 Avalanche 18, though from some of the shots it looks like the Havoc 18 (and Fi's 18's) might use the same 12-spoke basket as my driver so information from the new Havocs or any of the Fi woofers would likely be just as helpful to me. Yeah, 12-spoke "MTX" style basket rather than the 6-spoke basket shown on the archived Ava18 page. As for waiting, if possible I'd really prefer not to. I bought a broken one that's getting sent to Fi to be reconed before it gets to me. So driver's not going to be here for a little while, even with the frankly amazing turnaround time Scott quoted me, considering that it has to go 3/4 across the country lengthwise twice. Oh, and to further complicate things, I'm also moving at the end of the month. After I move I'll be too far away to ask my current cabinet-maker to deliver to me. So while I certainly realize it's not the ideal situation, it seems to me that it's my best option right now. However, I've had no luck finding the ???'ed information about any of those drivers. Particularly on the depth of the lip. Except for the Tymphany companies (Peerless/ScanSpeak/vline) and Seas, nobody seems to make that kind of detailed information readily available. Speaking of which, I'm curious: was a basket upgrade from the 6 thick spoke with no under-spider ventilation pictures on the archived page to the 12 narrow spoke with under-spider ventilation a running change to the Ava18? It seems like an upgrade over the 6-spoke basket pictured on the website, with the ventilation holes under the spider. This driver was mentioned as being from the closeout. As an aside, here's a picture of the driver I bought from behind, along with a basket shot of the TC Sounds LMS-5400 I assume replaced it in the PO's system: Isn't that an elegant-looking motor? Not the giant LMS-5400, which I'm sure works extremely well but is certainly more "imposing" than "elegant." The Ava's XBL^2 implementation just looks so purposeful, something there to do a job without being burdened by marketing conceits into excessive butch-ness. Like the Aura NRT motor or the related - knockoff? - "beehive" TC Sounds used in a few pro audio applications there's just enough structure to get the job done, but no more. My kind of design.

I'm a soon-to-be Ava18 user. However, I'd like to get the cabinet started before the driver arrives, so I can plug, play, and grin. So if someone could confirm the dimensions I have, and fill in the ones I'm missing, I'd appreciate it. OD (with gasket): 18.5" OD (sans gasket): ??? ID (cutout): 16.75" (edit) Height of driver lip (with gasket): ??? Height of driver lip (sans gasket): ??? Also, assuming the driver is recessed by .75" (mounted on the inner layer of a double baffle) how much clearance should I leave for the grille? (I plan to adopt a cat after I move, so I think a grille will be necessary to make sure that no claws touch the surround.) As for how I'll use it, just in case anyone's interested, it will provide the foundation for my primary multichannel audio system. (I'd call it a "home theater" except that it is used 70% for music, maybe 25% for the Daily Show/Colbert Report and football, and 5% max for movies.) It's replacing a Tannoy B475, which is also an 18" sub, but one with probably 7-8mm xmax and tuned to ~25Hz in a 168L enclosure. I'm going to put it in a ~150L net (19mm walls, 38mm baffle, well braced) sealed box made out of Baltic Birch and finished with Venetian plaster. (I know I could get considerably more output by going with a vented box, but ~110dB modeled at 20Hz is plenty for me and at heart I'm a low-Q sealed box guy whenever that will get me sufficient output.) It will be EQ'ed and powered by my current sub amp, a Crown XTi2000. The other speakers in the system are all Tannoys, 12" dual concentrics up front for LCR and 8" dual concentrics for surround.

Jesus...do you even use crossovers? Did you read the post you quoted? "Fc" stands for "crossover frequency," so I'm discussing a sub in the context of an 80Hz crossover. My receiver, a Panasonic XR55, happens to have a 2nd order slope if memory holds. But a crossover isn't a brick wall, remember. It's a slope, and there's considerable overlap even with a 3rd or 4th order crossover. So sub anomalies in the octave or two above the nominal passband are definitely audible. I don't know that the "Fc+2 octaves" thing is a very good rule. It, along with a few other things (low inductance that's linear with excursion is another that is too rarely discussed) is something that I've come to realize is important. At least at home. In a car it doesn't so much matter, because boundary issues so thoroughly dominate a car's sonic signature in the 150-300Hz octave.

Hmm. Chances are, if that Havoc 18 has a Faraday ring in the motor, low inductance, clean response out to ~400Hz*, and is competitively priced, my 12" Tannoy dual concentrics will have a new playmate! Anyone want to fill me in? *No, I don't plan on use it that high, but I've found that smooth response out to ~2 octaves above Fc is a crucial factor in whether or not I'll think a subwoofer is any good in a high-resolution home audio system; assume an 80Hz Fc, and that puts you out to 360Hz.

I thought that the quoted

Perhaps a stupid question, but I have the agility to convert units of a law student. Is the inductance of this driver 10.7mH or 1.07mH?

I don't know that the naysayers are right. It might be a good "halo" product, especially if the motor is really well done. Most of the antipathy to larger woofers stems simply from people not having heard such a thing. Just look at the market for 18's. Five years ago, outside of pro audio there was the Adire Maelstrom, JL Audio 18W3 and 18W6, and that was about it. Now it's a fairly standard part in most companies' lines. I wouldn't be surprised, now that 21" drivers are starting to be found in pro audio (B&C and P. Audio both recently announced and/or released some) if home audio follows suit. The finest bass driver I've heard to date was the 55cm Cabasse woofer, so a long throw, low inductance 20" woofer would be right up my ally. Even if it cost more than getting the same volume displacement from 15's or 18's.

Wow. This subwoofer looks like the volume displacement bargain of the century. It has almost twice the xmax of the old Adire Maelstrom ca. 2002, while coming awfully close to half the cost. Gotta love progress! At the risk of sounding ungrateful, what's the Le? Also, and considering the cost I have a feeling I know the answer (while also knowing that because of said Vd/$ ratio I might not care that much...) but it wouldn't happen to have a shorting ring in the motor, would it?