Its funny you say the XXX's efficiency is so bad, and the SX is 'moderate to high', yet even in David's test the SX only peaked about a db higher than the XXX (approx the same diff as from the SX to the MT). So I guess this makes this MT super super super efficient iyo? Efficiency is not the only name of the game in output, Im surprised to hear you speak like it is. One sub can be more efficient thereby having more output at a given input power level, but that does not mean its 'always' louder. The XXX has more power handling potential than the SX (which IS a benefit in ported applications), not just more displacement. The only real advantage Ive seen in output from the SX to the XXX is in the SX peaking higher, making it easier to burp those tones at your car's resonant freq. Beyond that, in my experience (have owrked with both drivers), the XXX gets louder. Sider by side, the XXX gets -clearly- louder playing music. I guess the applications Ive been around all fell into that 1% category?
Id love to se you prove an SX will always be louder (or 99% of the time) above 28hz (given similar installs).
Your xmax statements are waaaaay too general. Lets break them down. You said the XXX has more displacement, but how much power will it take and will it 'go thermal' before reaching its xmax. There's some interesting assumptions and key information left out of those examples though, right? //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif Such as, what box type are we speaking about. If its sealed, you cannot dismiss xmax figures so easily. Frankly sealed, XXXX simply owns an SX (according to specs, my ears, friends' ears, etc etc). Ported the SX does not have such a huge disadvantage, because as you stated, displacement potential doesn't mean -as much- ported. I wont agree displacement plays 'little to no role' in ported applications, as that's a statement only an SPL guy would make. If you are burping your vented system at or near tuning, for an SPL burp, yes displacement (xmax) means little to nothing, as thermal limits come into play. But your logic and reasoning ended there (and did not bother explaining that little detail). Change the situation a little bit, we are still using a ported system, but we are now playing music (what the XXX was designed for) instead of a single note burp near tuning. Now displacement starts playing a bigger and bigger role. The more you deviate from tuning in a vented system, the more con excursion comes into play. Cone excursion means little to nothing for SPL burps, but playing music is another story. Why'd you leave this out of your reasoning?
As for the thermal issue (you say a xxx WILL go thermal before reaching xmax... hence your 'there goes that wonderful displacement' comment), its strikingly biased against the XX also. I notice you dont mention (again) that you are obviously only referring to an SPL burp type situation when you say the XXX will go thermal before reaching its xmax (not to mention just about every other speaker on the planet... reaching xmax at tuning is extremly difficult). Or, are you trying to convince us you cannot reach full excursion potential with a XXX without it melting down 'in every circumstance'? Bo, of course you aren't, but I do find it interesting you skew all your examples to favor the SX and slight the XXX. Why is that?
Lastly, your statement than an SX 'does more' for less money is absurb. Again, only a comment an SPL head would make. If peaking louder is the only thing that interests you about a subwoofer, yes I can see where you'd say the SX 'does more' for less money and buying a XXX is merely for the hype. But when you start looking at it with something other than your tunnel vision (only setting up situations advantageous for SX and disadvantageous for the XXX), its clear the XXX holds many advantages over the SX. Clearly you are biasing your responses towards SPL, but you word them as if they apply to all situations. Your posts are very misleading in this regard.
