Sealed Loudspeakers?

Martin, I'm sure your product is very well thought out. And I'm sure every man & his dog would like to play with a woofer sporting 22.000 gauss...

Imagine a minimum phase design that uses a single differential gain block and 8-12 passive parts

?? Two channel gain stage with a line-level xover(perhaps with a contour)??
Cheers

In conclusion, look for any loudspeaker that uses a sealed box, seemingly stupidly large magnets, and an outboard bass processor. You'll be on the right road...

Agreed. Sealed box active sub woofers with large drivers that have large magnets...sounds like the ticket to me!

The TRW design scares me a bit due to turbulence of the blades creating audible noise above LF frequencies ...but it sure is innovative and that it works at DC I can well believe!

One reason I would never get rid of my gorgeous Avalon Ascent MKII's.Sealed 175 lb box,with two outboard 55lb crossovers.Very easy load(6 ohm),and amazing detail retrieval and timbres.Yes,I have added a big REL sub,as I have these speakers 8-9 feet out into room,and can use a drop of low end slam/depth,but the integration is flawless.
I truly believe the partnering electronics of the day was not up to this "classic" speakers performance match.Even the A/C power conditions are dramatically revealed with this wonderful design,which sounds a bit like a big Magico Mini.Every bit as revealing as the new(very nice,btw)Avalons,but better midbass,and lower midrange.It's the BIG external crossovers that proved to not have the best WAF,but the speakers(and crossovers,to me,anyway)are absolutely gorgeous in my tropical olivewood.
These appear once in a long while on the used market,and are a steal,at the usual asking price.Build quality is in the "heirloom" range.
Best!

You buy the New NSR Sonic Research with their patented
APL lens which is a sealed system that refocuses the soundwave for incredible tight Bass that is at least in the mid to low 20hz region cleanly for a speaker under $5k to do that and sound so cohesive on top is a breakthrough IMHO and many others at the shows including reviewers agreed.

Esp speakers are some of the best sounding speakers. The smaller models were some of the best at the RMAF.
As Glide3 said, they are sealed.