As he promised, Guttenberg reviews the Eminent Technology LFT-8c.

There are many paths up the mountain of good sound. If I had an 8B I would upgrade all the jacks and xover parts and wires with the best stuff (including 12 gauge wax foil coils that are cryoed and used in the best sounding direction.....going into the inside of the coil and out the outside). This would take them to a level that practically no one has ever heard. Then I would disconnect the woofer and on a separate flat open well braced baffle would mount either two Lii Audio or Acoustic Elegance 12 inch woofers and use a separate amp that has full eq to extend the woofs down to 20 hz and also get rid of all room nodes. I had the GR research servo woofs and they do not play above 150 hz even with the highest xover point. I always had a hole between the woofs and my planar speaker (heard and measured). Also you cannot equalize the bass with the servo system. I would use something like a Crown XTi 2002 to biamp. You run the mids and highs from your great normal amp and the woofs get their own amp with eq.....so they are driven directly with no coils.

You could also wait till next year when ET might bring out a speaker using the new 90db panels (not the two boxer he showed in Florida). This would need to have new woofers and bigger box on bottom to match. Also, I suggested to Bruce that he sell the new 90db drivers on the panel by itself.....with no woofers....so us DIY people can make our own super xover and bi-amp as described above. We will see what he does.

Here are some more ways to get tricked out planar sound:

Put two 12 inch woofs on an open baffle and above it mount 4 of the 8 inch planar drivers from Parts Express ($60 each...or optionally, use the way more expnsive Radian Planars)......now you have a 32 inch line source of planar drivers running from 300hz on up (high 90s sensitivity). You get the Minidsp Flex pure digital version...xover ($500) and make a super power supply for it.....and get two modified pure digital amps (VTV D300 or Peachtree GaN1) and use a stereo amp per channel mounted right behind the speaker. All xover and eq and delays done via the minidsp. This system would have no preamp, no DAC and no analog interconnects.....just some coax digital cables and very short speaker wires that are connected from the amps directly to the speaker drivers......this whole system with out streamer would be around $8-9K.....for everything including the wood for the baffle. Would be killer. Think about it.....No DAC, Preamp, analog cables, no long speaker wires. Xover and eq done totally in the digital domain......pure digital amps.....two state of the art 12 inch woofers per side and 4 highly efficient planars per side.....all perfectly equalized and time aligned for your listening position........

If you want to stay with analog class D or class A or whatever then you can get the new Danville dspNexus xover and bi or tri amp with it. Check out what Richard is doing at Hollis Audio Lab. He just showed a stack of 3 servo woofs and the mid/highs were a single planar 10 inch driver from Radian mounted on a small open baffle. He is now experimenting with adding a small tweeter to give better dispersion (tri-amping). Please check out his forum on Audio Circle. He has helped one person with ET speakers to use the Danville xover with it.

Damn Ric, you’re gonna scare off potential LFT-8b/c buyers!

Sure, an outright fanatic like Ric Schultz can concoct a Frankenstein LFT loudspeaker, but most audiophiles (including those reading this thread) are looking for a plug & play loudspeaker, not a complicated project. Heck, even building the Rythmik Audio/GR Research OB/Dipole Subwoofer is beyond the interest and/or capabilities of your "normal" audiophile. I found it to be relatively easy, and I’m no master cabinet builder.

The recommendation of the Eminent Technology LFT-8b/c was suggested as an alternative to the far more commonly known Magnepan planar-magnetic loudspeakers. In the opinion of myself and Steve Guttenberg, the LFT-8b is superior to the Maggies, only slightly higher in price to the clearly-inferior MG1.7i (I compared the two), and less than 1/2 the price of the MG3.7i. The 3.7i I have not heard, Steve has. Make of that what you will.

How would a set of 8b’s integrate with a swarm subwoofer system?

@peter_s: Very well. In fact, since the LFT-8b has limited response below 40Hz or so, it is an excellent candidate for add-on subs. And since the response of the woofer at 40Hz and above is unusually "fast"-sounding, it blends well with subs. I myself use a pair of Rythmik Audio F15HP subs (I bought the kit version, building my own 4cu.ft. enclosures), using them crossed over at 40Hz. I also built a pair of the Rythmik Audio/GR Research OB/Dipole Subs to use in place of the LFT-8b’s woofers, but that’s a story for another time.😉

The LFT-8b---having a sealed dynamic woofer for reproduction of frequencies 180Hz and lower---doesn’t suffer from the dipole cancellation found in full-range dipoles (such as Maggies). But an 8" dynamic woofer in a sealed enclosure---even one of the quality of that employed in the LFT-8b---can do only so much. Since the LFT-8b woofer is a monopole, there will be no discontinuity between it and a sub swarm also of monopole design.

Bruce Thigpen intentionally uses a higher-than-normal-mass woofer in the 8b (he in fact mass loads the driver), sacrificing the ability to play above 180Hz in exchange for better performance below that low crossover frequency. The LFT (Linear Field Transducer, invented and patented by Thigpen) magnetic-planar driver reproduces 180Hz up to 10kHz, with no crossover in that frequency band! That’s one major reason for the 8b’s unusually-high sound quality. Another is the LFT driver being of push-pull design (magnets on both sides of the Mylar diaphragm), in contrast to the single-ended Maggies such as the MG1.7i.

$3200 for the sound quality provided by the LFT-8b? You have to hear it to believe it!

There is no death......there is nothing to fear.

Here is a SUPER SIMPLE serious speaker. Buy a pair of the Lii Audio Platinum 10 inch full range drivers ($2200) and mount them on a four foot by 2 foot piece of multiply damped baffle and have four foot by 2 foot wings on the sides going back. Now you have a full range open baffle speaker that costs around $2500 for the drivers and wood and is 100 db efficient and when properly burned in and wired directly from your amp to the voice coil wires.....will sound incredible....You should get close to 40 hz in room with no eq. You could build a test baffle in one afternoon and start enjoying them while they burn in. My friend has the Silver 10s mounted on the above mentioned open baffle and he gets 40 hz flat in his room. He did mount an AMT on top with a copper foil cap to make it even better. His drivers are $1200. He goes to shows and the only thing he likes better at a show than what he has are the expensive silver Supreme Borresen speakers driven with 100K worth of stuff. He uses a tube amp he built himself. Plenty ways up the mountain of great sound.

You might want to check out the wild horn loaded cabinet that Decware designed for the Platinum speaker driver. There are sound bites on You tube. He does not wire directly to the voice coil wires.....he uses the junk binding posts on the speaker and probably another binding post on the front of the speaker (not good...he is not much of a tweaker). But his cabinet is way cool.