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Eminent Technology LFT-8b in Harry's system

I recently signed up for the V.P.I. Industries newsletter, and today received my first such. In it, Harry Weisfeld reviews a Grado phono cartridge, but this post concerns one of the speakers he listed as being those he uses to listen to music and evaluate recordings through. All but one are traditional dynamic cones/domes in a box designs, only one being a planar/dipole. That planar is the Eminent Technology LFT-8b. I'm pretty sure Harry could, if he so chose, have instead as his sole planar a pair of $6000 Magneplanar MG 3.7i's, or even $14,000 20.7's. But nope, he instead chose the $2500 ET LFT-8b, imo the greatest value in a loudspeaker on the market. I compared it to the 1.7i, and the difference was dramatic.
bdp24
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bdp24 OP
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Yup, ESL’s are IT for transparency imo. I have QUAD ESL’s, Stax phones, and a pair of ESS Transtatic’s with three of the RTR ESL tweeters, I’ve heard the big Soundlabs, and had I the requisite space and funds would have a pair of them too!

The impedance modulus of the LFT-8b is a good point to bring up. Thigpen says he could give the speaker any impedance he wanted, and chose 8 ohms. The LFT panels themselves are 11 ohms (and mostly resistive in nature), and may be bi-amped separately from the woofer (two sets of binding posts are provided).

The earlier full-range LFT models (LFT 3, 4---which I also own, and 6) are 4 ohms, like Maggies. The 3 and 6 are bi-ampable (at 400Hz, I believe), so a tube amp could be used with a big ss amp for the bass.

The LFT driver is much more robustly-built than the somewhat-garage-ish construction of the Maggies. The substantial metal driver frame is bolted into a cutout in the solid oak speaker baffle, whereas the Maggies have no metal driver frame, the Mylar being merely glued (and stapled?) onto the MDF (yuck) frames. The LFT is also a push-pull design, one reason listeners find it to be a very low distortion-sounding design, closer in sound to an ESL than to the Maggies.

scothurwitz
113 posts
 
I’ve never owned Magnepan Tympani’s but I did own their 3.7i’s for 3 years and really thought they were a great speaker. I also tried a pair of their DWM woofers and that was a fun speaker system. lewm spoke highly of their ribbon tweeter, I thought that true ribbon tweeter was one of the best tweeters I had ever heard, the high frequency extension on that tweeter was insane. My room was not as big as I would have liked (17’ x 12’x 8’ ceiling) but after much trial and error (mostly error) I finally found the “right” spot and then they loaded the room amazingly well. The right side of the frame was only 16” from the wall to the right of the speaker and to my surprise and delight it worked. I have always wondered what they would have sounded like if I could have got them 2 - 3’ from the side walls? I have noticed a lot of guys on this forum comparing the LFT8B’s to the Maggie 1.7’s. I now own the LFT8B’s and prefer them over the 3.7i’s, I don’t think the 1.7’s are even in the same ballpark (other then the price). In my opinion, there are very few speakers, regardless of price, that can rival the LFT8B’s. 

Scot
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bdp24 OP
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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 ;-) . 
pryso
1,985 posts
 
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.
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bdp24 OP
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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!
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