Quote Originally Posted by kexodusc
Wooch, I've also confirmed that the Q alignment of the Titanic MKIII kits is 0.707...you could argue the real impact this produces, alot of subs seem to be going for higher Q's these days, the Q itself is meaningless, though, you have to take the parameters of the driver into consideration. My guess it was just an easy place for Vance Dickason to start.

The 12" driver produces a swept volume at 1.67 L by my calcs, though the Dayton driver measures only the effective radius of the driver, not sure if the Rava specs use the larger radius figure to boost the reported specs or not.

The 12" Dayton is the more efficient driver (not by much), but coupled with the larger amp I think you'd maintain see a bit less distortion at higher SPL...how much real world advantage this translates into is beyond me though, probably not much. It might actually be more of a benefit at lower SPL? I'm not really a sub guy, spend most of my time on crossovers and speaker cabinets.

Alot of would people argue you need the better (bigger) amp to take full advantage of the excursion both of these drivers...though I'm not sure utilizing full excursion capability is always necessary.

I've never heard the Rava personally, though I've heard of it often enough. It could be the better performing sub of the two, or even just a more affordable alternative that captures most of the performance at a better value...I know my parents 12" MKIII kit is noticeably lower, and leaner than my PW-2200 was in my room, but alot cheaper...I have high expectations for the 15" kit (almost double the surface area of the 12" and sweeping over 3 L, here I come)...

Thoughts?
Very interesting indeed! Sounds like the MKIII driver's a nice step up over the Shiva, which would then justify its higher price. With the new driver specs, that answers my question about the differences between the two. The driver and amp used in that Titanic kit would alone cost about $440, while the Rava costs $400 fully assembled. I would expect and hope that a $540 kit can outperform the Rava, otherwise what's the point?

The Rava uses that Q=0.67 alignment and they modified the amp with both a rumble filter and an EQ circuit that's supposed to flatten out the response (I believe that the 250 watt amp used by Adire is a pretty generic design that just about every DIY sub supplier sells some version of). Choosing the Rava three years ago was a pretty easy choice, because it was pretty much the only option that matched what I was looking for (at that time, I did not consider DIY an option because I'd never owned a sub before and didn't want my first foray to incur more complications than there already were). Now, with more comparable choices out there, this is a great time for people looking for an affordable sealed sub option.

As far as your kit goes, have fun with it and let us know how it goes! But, just to muck things a bit more for your bout of upgradeitis, you should get a look at Adire's 15" Tumult driver. That thing has a linear excursion of 3.4 cm one way and Adire claims a swept volume of over 5 liters! Acoustic Visions is the only company I'm aware of that currently builds finished subs around the Tumult driver, and they start at $1,500 (the driver itself costs $500). See how long you can resist!

http://www.adireaudio.com/TextPages/...eFrameText.htm