Eminent Technology LFT-8b in Harry's system

In the LFT driver, Bruce Thigpen found a solution to many of the shortcomings audiophiles have long considered Maggies to have. It's too bad more of them can't hear the LFT-8b, buying the 1.7i not knowing what they could have for only a few hundred dollars more. Brooks Berdan carried the ET speakers as his only planars, but made a lot more money selling Wilsons ;-) . 

Scot: "been around for over 3 decades and in all that time I believe he has made only one change to the design".

I'm not an authority on the ET speakers but if they went from LFT-8 to 8a to 8b then I imagine there must have been two changes sufficient enough that Thigpen made a model change.  And there could have been minor changes not in themselves warranting a model change.

But I think your basic point that the design survived more than 30 years with minimal changes speaks to the brilliance of that design.

I'm not in the market today, but if I am again I will certainly consider the ETs, thanks to bdp's posts along with others.

Yes, the "a" update addressed issues with the ribbon tweeter's x/o (but not the tweeter itself), the "b" the 8" dynamic woofer.. You’ll notice that the LFT (Linear Field Transducer) magnetic-planar driver itself---which handles frequencies 180Hz through 10kHz, with no cross-over---has remained unchanged for over 30 years!

BTW, Harry Weisfeld now has Apollo 12 loudspeakers in his home in his reference system. Apollos are an AMT based line array.

With the Covid stay at home order in MI I decided to play around with the .6MH inductor.  I tried the new Jantzen copper foil in wax 14 gauge, which is all the rave.  Sadly, it thinned out the mids with maybe a slight increase in detail.....btw I hooked them up in both directions and they were worse than Bruce's stock 18 gauge magnetic wire air cores which are very good. I debated on ordering the 12 gauge copper foil in wax but decided to go with the Erse XQ 14 gauge perfect lay air coiled inductors.  I'm glad I did as the moment I hit play the mids sounded rich and full like a good tube amp.  The detail was all there and so were the highs.  I did A/B Bruce's inductors and easily identified the Erse's every time.....by the fat juicy midrange.  If you have a large room and are looking for more meat in the midrange than the Erse's are the ticket.   Funny how the change in wire gauge(DCR) can make such a big difference in the mids.  I think the inductor switch is just as significant as changing the 470uf and 4.7uf cap.