Eminent Technology LFT-6s

Years ago–don’t know exactly when–Bruce Thigpen and his Eminent Technology company designed, made, and sold a model LFT-6.. It was and is a full-range mag-planar speaker with separate bass, midrange, and treble drivers, all on a ‘solid’, hardwood panel that is 6-1/2 feet tall and 18 inches wide..

Bruce told me that they didn’t sell well because they had not enough bottom-octave energy and were a tad expensive–like maybe $15K per pair in current dollars.. This thread…

…caught my eye, and after many e-mail conversations, Bruce agreed to build a pair for me.

They’re a foot taller and 5 inches wider than the LFT-8Cs so will fit VERY well in my room, even with the ET LFT-8Cs rotated out of the way.. Things I love about the design are:

  1. Physically, all drivers are in the same vertical plane and electrically in the same polarity and therefore are in phase;
  2. All the x-over filters are single-order, therefore keeping the signals in phase, at least for much of their filter slopes; and
  3. There are only FOUR filtering devices in the entire x-over network.

They’ll require at least three months to build, etc., which fits well with my fall project to remodel my musicroom. THIS is exciting. :grin:

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Had Sonic Craft send Bruce two trios of Mundorf EVO Oil caps (totaling 470uF per trio) for the MR-hi-pass filter, and I’ll be supplying ET with Neotec 18- and 22g. UP-OCC-copper-in-Teflon wire for the MR and tweeters.

ET is building Sound Anchor-type stands for these speakers.

Also chose and sent to Bruce the SoniCap Platinums for the tweeter hipass filter.. Bruce told me they had fashioned a crossover board of solid walnut; that ought to look good. :slightly_smiling_face: I might have these by Thanksgiving!

FWIW, here are 3 pics of my new/old LFT-12B centerchannel speaker, made of solid-3/4” walnut panels.

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We’re down to the last pair of caps (for the tweeters) that will get there Tuesday the 12th.. ET is building wooden crates to ship these via truck-freight.. They shoud be shipped by the end of next week (the 14th).

Meanwhile, I’m having my left-shoulder joint replaced Wed. the 12th. :persevering_face: :smirking_face: I guess someone else will unload and install these for me.

Have received a used pair of Schiit Tyr monoamps that are burning in.. Have decided to sell my pair of BHK600s which run WAY too hot for me and have about 400 Watts more power than I need and also my pair of Atma-Sphere MA-1s which also run WAY too hot; I still have my pair of somewhat-improved M1200s and my P20 which just runs and runs… :grinning_face: .

Interesting you find the BHK 600’s run hot for you. Yes, they get warm but don’t change the room temp and you can touch the heat sinks without duress. My experience with Class A amps of decent wattage is that they can affect the room. Hope things work out for you.

SW, my BHK600s run hotter than ANY other class-AB, nonvacuumtubed amps I’ve ever had, and I’ve had MANY hi-power amps.. The Schiit Tyrs run so cool that one can hardly determine, by holding the heatsinks, that they’re turned on.. Also, the ‘600s are the finest-sounding class-AB amps I’ve ever heard on my VERY-fussy-about-amplifiers Sound Lab Majestic 745s(1).. The BEST-sounding amp of any kind I heard driving the SLs were a pair of Pass XA-60.8 class-A amps.. I never had access to my VERY-hot-running Atma-Sphere MA-1s while I had the Sound Labs.

Assuming the Tyrs continue sounding excellent, I’m finished shopping for poweramps

(1) The all-mag-planar Eminent Tech. LFT speakers, having quite benign impedance characteristics, are very tolerant of poweramps.. I believe it was the Sound Labs’ very low impedances (1 to 2 Ohms) in the treble region that caused most poweramps to sound grainy.

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ET has shipped the small parts a few days ago via FedEx; the large panels will be coming via truckfreight.. Haven’t seen anything about that shipping date so, probably, I’ll not see these this week starting the 17th… Oh well, more time for my replaced left-shoulder joint to heal.

The Schiit Tyrs are still burning it…have about 200 hours on them; system (with the ‘8Cs) sounds EXCELLENT.

The ‘6s are arriving Wednesday the 3rd, which will make the production-and-shipping time almost exactly two months.. I decided a week ago to try a pair of Parasound JC 1+ monoamos–these of the 450-into-8 variety–and they arrived over the WE.. Because they are direct-coupled–that is, have NO coupling capacitors or inductors–they broke-in quickly and already sound EXCELLENT driving my LFT-8Cs.

I’m really getting excited about this. :grin:

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The ‘6s arrived this morning the 4th with NO notification.. They were left on my garage-door sidewalk, and the sort-of-one-piece-pallet-and-crates is so heavy I could hardly lift one end with a fairly HD handtruck.. Have someone coming over at noon to help dismantel the crating to get the speaker boxes into the musicroom.. As U probably can tell, I’m rather annoyed with this freight outfit.

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Please upload photos of the speakers once set up. New speakers are exciting. Have fun

Because the overall sounds were rather midrangey, I played with padding down the MR drivers with Mills noninductive, wirewound 12Watt resistors; IIRC–it was yesterday evening, after all–the two installed in series sum to just over 1Ohm for about 2dB of decrease. Will be trying 1-1/2 to 2 Ohms for 3 to 4dB tonite.

The overall sounds are VERY resolved.. Have reinstalled one of my c. 5x3.5-foot basstrap panels behind the right-channel speaker; I think I’ll remove that and reinstall the four diffuser panels stacked to the right.

Friday edit–removed the basstrap panel; probably I’ll reinstall the diffusion panels on that front wall.

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By Friday evening, I had increased the ‘padding’ of the MR drivers; my prior calc was wrong, and after adding a couple sub-1Ohm resistors, the decresse in MR output is c. 2dB.. The ‘midranginess’ has mostly disappeared, and the overall tonality is close to perfect FOR ME.. Have more of those sub-5-Ohm Mills resistors on the way for fine-tuning.. FWIW, ET’s use of a terminal strip to connect the separate x-over board to the panels makes it VERY easy to do this playing with resistors to adjust the systems’ tonality.

With about 30 hours of 24-hours-per-day break-in, these speakers already sound EXCELLENT.. The soundstage is taller…DUH!…and, I think, a bit wider and deeper than that of the ‘8Cs, with NO false-large-instrumental ‘images’ in the soundstage.. For whatever reasons, they are MORE resolving than the ‘8Cs, and I LOVE that!!! While I’m absolutely NOT a golden-eared audiofile (GEA), perhaps I’m up to bronze-eared musiclover by now, and I’ve heard more ‘tiny’ bits of music in extremely familiar music than before.. And just as a reminder, these speakers use the highest-quality caps I chose to afford–at a replacement cost of well over a thou$and dollars for the tow or three (depending on what one is counting) per channel, and considering that the majority of the music coming thru these speakers flows thru those Mundorf EVO Oil MR-hi-pass cap-combinations, it was money well spent.. And I might try bypassing the EVOs with a pair of 6.8uF SoniCraft Platinums* that I have; good thing I have plenty of alligatorcables.

These are definitely keepers for me, and my ‘8Cs will be posted For Sale soon.

…and the Parasound JC 1+ monoamps sound better than ever. :grin:

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