LMT, LMS... same thing just different time periods. You're right though, it's horribly inefficient and has a relatively high moving mass.
And Sancho, it's really not that great a great woofer... for those concerned with high output. But as far as musicality is concerned it's among the best. That high moving mass combined with a somewhat soft suspension yields an incredibly low Fs of around 15Hz, but the trade off for that wonderful soft spider is a high Vas figure and subsequent need for a large enclosure, as was pointed out. Why do I say a soft spider is wonderful? Because they're easy to drive, don't make a ton of mechanical noise, and they effortlessly release the rich harmonic complexities and other details in music even at low listening levels. Large enclosures help with that also, why do you think infinite baffle sounds so good? Anyway, combine that Fs of 15Hz with an ultra-quiet three inch mechanical stroke, very low inductance, one of the lowest distortion figures attainable, and you'll hear one of the most musical subwoofers ever and it only sounds better the lower in frequency it goes. Just as it should be when describing a subwoofer. So you need lots of power to get the same output, big deal. Power is cheap and there's no free lunch. The sensitivity was sacrificed for the linearity. The only way to get it back would have been to put an even bigger magnet on it. So really the only true downside is the need for large enclosure. Some people can afford it, some people can't. This driver simply reminds us of why it's important to have goals and know how to choose which drivers will fit the bill. This driver is music first. If you need more output, use more of them.
It is inefficient, with a generally high mms. Also will likely need a fairly large box to extract the best out of it. Lots of ferrite so it looks cool though
