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Eminent Technology Now Has A Dipole DSP Controlled Woofer for the LFT-8C

108.245.106.95

"The LFT-8c gradient dipole woofer represents the most significant improvement to the LFT-8 loudspeaker since it's inception."
"The LFT-8c update adds a powered dipole woofer with DSP and the ability to smooth the low frequency response of the speaker in any listening room, time align the woofer with the midrange/tweeter, and improve the blend between the midrange/tweeter assembly with the new woofers."

Sorry if this has been posted before, however it's new to me
New dual cavity enclosure with forward 8" and rear 6.5" firing woofers
$1,600 for the updated woofers

http://www.eminent-tech.com/LFT-8cwooferupdate.html (Open in New Window)

Edits: 02/05/23

Follow Ups:

RE: Eminent Technology Now Has A Dipole DSP Controlled Woofer for the LFT-8C - sbrook 06:15:13 02/10/23 (6)
I generally stay out of a pile on but as seemingly one of the few current owners of an ET8x system on AA I will engage...

My perception of Bruce is generally that he is an engineer seeking good sound. As a designer and manufacturer of what by mortal income standards is high-end audio I find his marketing rhetoric to be no-where near the babel bs level of most boutique companies. Some of the discourse in this thread would seem to accuse him of outright lying about the design of this woofer system based on what are in essence, blurbs.

In my ignorance I have always thought of the fundamental difference between dipole and bipole as defined by the phase relationship between the forward and rear firing signal (wave?). I understand this is perhaps an over simplification of how these approaches are implemented and their design objectives for a given system but is the notion that this is not a "true" dipole relevant to the picayune criticisms of how he is advertising it? Is there a serious concern that Bruce trying pull the wool over someone's eyes?

The changes to the LFT8 design have been incremental over several decades. When I upgraded my 8a with the 8b tweeters I heard everything that Doug Schroeder observed in his detailed comparison at that time and it dovetailed with my perceived deficiencies of the system prior to changing the tweeters. Regardless the marketing and product description of the 8c woofer upgrade I would be shocked if it didn't make the system better.

The above being stated, does this elevate the 8c to a $4500 speaker system? Does it make this a must buy $1600 upgrade for 8b owners? Not to me. Both the money that I don't have to spend on it and the additional complexity of wiring and working with DSP do not appeal to me. Running my 8b as I do, full range, with a B&W ASW1000 crossed in at 40Hz and almost no gain give me all the bass I need. I am sure if my room was meticulously measured there would be all sorts of anomalies but I if I can't hear it and the music sounds good then I have plenty of other things in life to be tortured over.

I would love to read a detailed review of a LFT8c or upgraded 8b but beyond that I remain content and free of upgraditis (thank the audio gods).
- Dipoles - grantv 18:40:49 02/10/23 (5)
  The majority of the discussion was understanding the wording he used (gradient being a key word), and if the design is or isn't a true dipole. Some may have questioned the wording for sure, but I don't see anything intentionally misleading. Bruce seems like a solid guy.
  - And for some... - E-Stat 07:10:31 02/11/23 (4)
    it's a life or death matter! ;)
    - RE: And for some... - Davey 08:01:37 02/11/23 (3)
      No, certainly not life or death. That's just silly rhetoric. But just what I expect from you.
      
      It's an interesting design, but I think it's important to drill down through the marketing-speak and use language that's accurate and clear.
      The audiophile world has become full of self deception and intellectual dishonesty.
      
      Dave.
      - RE: And for some... - TitaniumTroy 18:39:42 02/11/23 (2)
        
        In Reply to: RE: And for some... posted by Davey on February 11, 2023 at 08:01:37
        
        Davey, if implemented correctly how much of a improvement do you think the new woofer would be? Or is that too much mental gymnastics, as in who knows?
        
        RE: And for some... - Davey 05:40:23 02/12/23 (1)
        
        In Reply to: RE: And for some... posted by TitaniumTroy on February 11, 2023 at 18:39:42
        
        I dunno. I don't see much point in this configuration. If wanting to implement a dipole woofer, why not just build a dipole woofer? :)
        You wouldn't need a box(es)....you could use a single driver....etc, etc.
        This is a complicated way to generate a "directional" woofer system that may or may not work well in a variety of setups. Dipole woofers might have a similar issue, but they're much simpler in concept and implementation.
        I think this is probably an improvement over the old LFT-8 woofer system, which has a couple of significant issues.
        
        Dave.
        
        Edits: 02/12/23
        
        RE: And for some... - TitaniumTroy 16:08:10 02/12/23 (0)
        
        In Reply to: RE: And for some... posted by Davey on February 12, 2023 at 05:40:23
        
        Thanks
RE: Eminent Technology Now Has A Dipole DSP Controlled Woofer for the LFT-8C - E-Stat 14:34:49 02/06/23 (39)
I applaud the introduction of a true dipole woofer section but find it odd that the drivers are different sizes!

Pretty sure Linkwitz always used pairs of the same driver.
- Gradient dipole. - grantv 06:55:25 02/07/23 (8)
  It's described as gradient dipole, I get that.
  Gradient, as in partial/not full, on a grade toward (being a true dipole) as it will.
  And the design is not a true dipole. I don't see it being possible for Bruce to have met his goal with a true dipole in such a small package as this.
  - Hopefully - E-Stat 06:57:44 02/07/23 (7)
    Magnepan's effort with the "condo" model will be better and not make false claims.
    - The condo unit. - grantv 08:10:05 02/07/23 (6)
      Eventually I'm sure.
      False claims? You're referring to Bruce stating it's a dipole? He did state gradient dipole.
      - The following text was *not* qualified... - E-Stat 08:18:01 02/07/23 (5)
        
        In Reply to: RE: The condo unit. posted by grantv on February 07, 2023 at 08:10:05
        
        "The LFT-8c update adds a powered dipole woofer with DSP and the ability to smooth the low frequency response of the speaker in any listening room, time align the woofer with the midrange/tweeter, and improve the blend between the midrange/tweeter assembly with the new woofers. "
        
        RE: The following text was *not* qualified... - Davey 08:45:55 02/07/23 (4)
        
        In Reply to: RE: The following text was *not* qualified... posted by E-Stat on February 07, 2023 at 08:18:01
        
        Maybe you'd like to qualify your false statement these are "true dipole" woofers? :)
        Nah, I didn't think so.
        
        Bruce does not use that designation at all on his website. He does use the term "gradient" multiple times. That term, by definition, would designate these as NOT true dipole woofers.
        
        Dave.
        
        I did not initially assume - E-Stat 09:04:15 02/07/23 (3)
        
        In Reply to: RE: The following text was *not* qualified... posted by Davey on February 07, 2023 at 08:45:55
        
        Maybe you'd like to qualify your false statement these are "true dipole" woofers? :)
        
        they lied through their teeth as you suggest.
        
        Bruce does not use that designation at all on his website.
        
        Except when he does. :)
        
        RE: I did not initially assume - Davey 09:08:16 02/07/23 (2)
        
        In Reply to: RE: I did not initially assume posted by E-Stat on February 07, 2023 at 09:04:15
        
        Yeah, but he doesn't.
        Direct my attention to the word "true" on his page please. I just did Ctrl-F.....I don't see it.
        
        BTW, I consider lying through their teeth and marketing-speak to be two different things.
        
        Dave.
        
        I'll leave you with your argumentative predilection... -nt - E-Stat 09:11:07 02/07/23 (1)
        
        In Reply to: RE: I did not initially assume posted by Davey on February 07, 2023 at 09:08:16
        
        RE: I'll leave you with your argumentative predilection... -nt - Davey 09:13:40 02/07/23 (0)
        
        In Reply to: RE: I'll leave you with your argumentative predilection... -nt posted by E-Stat on February 07, 2023 at 09:11:07
        
        You used the word, I didn't. Now you're tap-dancing backward.
        Classic!
        
        Dave.
- RE: Eminent Technology Now Has A Dipole DSP Controlled Woofer for the LFT-8C - Davey 14:55:39 02/06/23 (29)
  That's because it's not really a dipole.
  
  Read the description dude.
  
  Dave.
  - Really? - E-Stat 15:02:44 02/06/23 (28)
    Read the description dude.
    
    Let's read it together, shall we?
    
    "The LFT-8c update adds a powered dipole woofer with DSP and the ability to smooth the low frequency response of the speaker in any listening room, time align the woofer with the midrange/tweeter, and improve the blend between the midrange/tweeter assembly with the new woofers...DSP provides signals for the forward firing 8 inch woofer and the rear firing dipole woofer . "
    
    Since you want to argue, direct your efforts to Eminent Technology.
    - RE: Really? - Davey 16:49:28 02/06/23 (27)
      You're reading it 'literally' and not understanding the description of what Bruce has created there.
      
      I suggest to try again.
      
      Dave.
      - Which continues to illustrate - E-Stat 17:40:29 02/06/23 (11)
        
        In Reply to: RE: Really? posted by Davey on February 06, 2023 at 16:49:28
        
        you're argument remains with their assertions.
        
        There's no *me* in this at all.
        
        Honestly, I couldn't give a crap. :)
        
        Honestly, I couldn't give a crap. :) - Davey 18:04:59 02/06/23 (10)
        
        In Reply to: RE: Which continues to illustrate posted by E-Stat on February 06, 2023 at 17:40:29
        
        Well, that's been obvious for quite awhile.
        
        Dave.
        
        You know what you have to do now - E-Stat 18:26:52 02/06/23 (9)
        
        In Reply to: RE: Honestly, I couldn't give a crap. :) posted by Davey on February 06, 2023 at 18:04:59
        
        Contact E-T and read them the f...ng riot act!
        
        How dare they make such baseless claims when I can refute them in but a single paragraph! ;)
        
        RE: You know what you have to do now - Davey 18:46:43 02/06/23 (8)
        
        In Reply to: RE: You know what you have to do now posted by E-Stat on February 06, 2023 at 18:26:52
        
        Why do you post about things you have no interest in learning about??
        
        "Dipole", like many things in audio, has become a squishy term used (not uncommonly) for marketing purposes.
        Heck, even you got carried away and called it a "true" dipole.....even though that label is not used at all on the website information.
        But, I assume that after reading the info, you would now stipulate it's not a "true" dipole, and you were yet again confused??
        
        Dave.
        
        I have often wondered why there is a dearth of dipolar hybrids - E-Stat 19:04:27 02/06/23 (7)
        
        In Reply to: RE: You know what you have to do now posted by Davey on February 06, 2023 at 18:46:43
        
        Perhaps that trend continues.
        
        RE: I have often wondered why there is a dearth of dipolar hybrids - Davey 19:14:32 02/06/23 (6)
        
        In Reply to: RE: I have often wondered why there is a dearth of dipolar hybrids posted by E-Stat on February 06, 2023 at 19:04:27
        
        The reason there are many hybrid systems is obvious.
        It's because they're so much easier to design and implement. (And better WAF as well.)
        1. Many contemporary woofer drivers (motor wise) are much more suitable for box usage vice free air.
        2. The equalization chore (if there is any) is much more straightforward.
        3. For a given SPL and same driver, box speakers have an approximate 4:1 advantage in Sd * Xmax requirement.
        And I could go on.
        Dave.
        
        Edits: 02/06/23 02/06/23
        
        But... - E-Stat 05:50:29 02/07/23 (5)
        
        In Reply to: RE: I have often wondered why there is a dearth of dipolar hybrids posted by Davey on February 06, 2023 at 19:14:32
        
        The reason there are many hybrid systems is obvious.
        
        That wasn't my question. Look up again at the title to which you responded. Martin-Logan doesn't use dipole woofers. Sanders doesn't use dipole woofers. Final doesn't use dipole woofers.
        
        Only E-T advertises using dipole woofers. Multiple times at that.
        
        RE: But... - Davey 07:52:12 02/07/23 (4)
        
        In Reply to: RE: But... posted by E-Stat on February 07, 2023 at 05:50:29
        
        Do you think there's a dearth of hybrid systems?
        
        Dave.
        
        Maybe third time's a charm! - E-Stat 07:56:27 02/07/23 (3)
        
        In Reply to: RE: But... posted by Davey on February 07, 2023 at 07:52:12
        
        Do you think there's a dearth of hybrid systems?
        
        RE: Maybe third time's a charm! - Davey 08:20:38 02/07/23 (2)
        
        In Reply to: RE: Maybe third time's a charm! posted by E-Stat on February 07, 2023 at 07:56:27
        
        You just mentioned a few of the many dipolar hybrid systems in your previous post. :) It seems you're getting yourself turned around again.
        
        Let me just state it clearly so you can understand. In my opinion, there is NOT a dearth of dipolar hybrid systems. There are numerous dipole-top monopole-bottom systems out there.
        And, I just outlined a few of the reasons why they are not uncommon.
        
        Maybe you don't understand the meaning of the word "dearth"??? I guess that might explain your comment.
        
        Dave.
        
        You still don't get it... - E-Stat 08:57:01 02/07/23 (1)
        
        In Reply to: RE: Maybe third time's a charm! posted by Davey on February 07, 2023 at 08:20:38
        
        You just mentioned a few of the many dipolar hybrid systems in your previous post. :)
        
        Only at the top. The entirety of this thread is about dipole woofers.
        
        Both Sanders and Final Audio employ but one woofer so scratch them. Martin-Logan has multiple dual woofer versions but none are touted as dipoles. The flagship Neolith crosses the 15" at 60 hz with the 12" between 250 hz and 400 hz.
        
        There are numerous dipole-top monopole-bottom systems out there.
        
        Just not fully dipolar!
        
        RE: You still don't get it... - Davey 09:04:38 02/07/23 (0)
        
        In Reply to: RE: You still don't get it... posted by E-Stat on February 07, 2023 at 08:57:01
        
        So, when you were talking about a "hybrid" system, you were really talking about hybrid-hybrid systems? What about hybrid-hybrid-hybrid systems?
        
        Hilarious, but I gotcha now! :)
        It's always an entertaining treat.
        
        Dave.
      - My reading is that it is Bipolar - 13th Duke of Wymbourne 17:10:28 02/06/23 (14)
        
        In Reply to: RE: Really? posted by Davey on February 06, 2023 at 16:49:28
        
        but the front and rear levels/phases are manipulated to form a modified dipole pattern.
        
        This sounds similar to the bass sections of the more recent Martin-Logan electrostats. nt. - MWE 06:57:11 02/07/23 (2)
        
        In Reply to: RE: My reading is that it is Bipolar posted by 13th Duke of Wymbourne on February 06, 2023 at 17:10:28
        
        Nt.
        
        Mark in NC
        "The thought that life could be better is woven indelibly into our hearts and our brains" -Paul Simon
        
        Very similar - jimbill 09:37:37 02/08/23 (1)
        
        In Reply to: RE: This sounds similar to the bass sections of the more recent Martin-Logan electrostats. nt. posted by MWE on February 07, 2023 at 06:57:11
        
        My 13a's have two 10" woofers in separate sealed chambers, 300w class D amps, DSP, and ARC. They produce very tight and fully integrated bass.
        
        And, if I'm not mistaken, a sliding-phase scheme like apparently the ETs have. nt. - MWE 07:06:42 02/09/23 (0)
        
        In Reply to: RE: Very similar posted by jimbillh@hotmail.com on February 08, 2023 at 09:37:37
        
        Nt.
        
        Mark in NC
        "The thought that life could be better is woven indelibly into our hearts and our brains" -Paul Simon
        
        RE: My reading is that it is Bipolar - hahax@verizon.net 21:04:26 02/06/23 (7)
        
        In Reply to: RE: My reading is that it is Bipolar posted by 13th Duke of Wymbourne on February 06, 2023 at 17:10:28
        
        +1. I agree it is a bipole but with the miracle of DSP it simulates the performance of a modified dipole. It isn't quite like a classic dipole. I assume the designer thought he could improve classic dipole dispersion with this design and DSP.
        
        And there may be another advantage to this design. Each driver is in an enclosure so the total design doesn't seem to need the massive equaliztion and power needed by a classic dipole. It will need some since the 2 drivers will cancel where their wave forms meet and are out of phase but I suspect the enclosures reduce the normal equalization. Thoughts?
        
        RE: My reading is that it is Bipolar - josh358 16:30:56 02/07/23 (5)
        
        In Reply to: RE: My reading is that it is Bipolar posted by hahax@verizon.net on February 06, 2023 at 21:04:26
        
        The amount of dipole equalization depends on the path length between the drivers, so having two independent enclosures doesn't directly affect that (it will affect the behavior of the drivers, but you would use drivers with different Thiele-Small parameters, so it's moot). But the fact that there are two enclosures suggests that this is no simple dipole -- if it were, there would be no reason to waste the back waves.
        
        RE: My reading is that it is Bipolar - TitaniumTroy 17:19:24 02/07/23 (4)
        
        In Reply to: RE: My reading is that it is Bipolar posted by josh358 on February 07, 2023 at 16:30:56
        
        Now we just need a forum member to upgrade his ET8's with the woofer and get some feedback on how well it works.
        
        RE: My reading is that it is Bipolar - TitaniumTroy 17:22:17 02/07/23 (3)
        
        In Reply to: RE: My reading is that it is Bipolar posted by TitaniumTroy on February 07, 2023 at 17:19:24
        
        LFT-8C I meant
        
        RE: My reading is that it is Bipolar - josh358 07:57:14 02/08/23 (2)
        
        In Reply to: RE: My reading is that it is Bipolar posted by TitaniumTroy on February 07, 2023 at 17:22:17
        
        Davey had one, but IIRC he sold it.
        
        RE: My reading is that it is Bipolar - Davey 08:39:20 02/08/23 (1)
        
        In Reply to: RE: My reading is that it is Bipolar posted by josh358 on February 08, 2023 at 07:57:14
        
        Yeah, I sold the speakers a few years ago.
        The problem with that speaker is the woofer and woofer crossover filter.
        I did a fix that 90% eliminated the problem, but it's beyond the average audiophile to implement it.
        
        I suspect part of the reason for the change in this speaker is the availability of the (modified) Peerless 8" driver, in small quantities.
        
        I don't think ET sells too many of these speakers anyways.
        
        Dave.
        
        RE: My reading is that it is Bipolar - josh358 23:44:46 02/09/23 (0)
        
        In Reply to: RE: My reading is that it is Bipolar posted by Davey on February 08, 2023 at 08:39:20
        
        AFAIK only Magnepan and Martin Logan sell planars in quantity.
        
        I remember when you fixed the crossover.
        
        Maybe it is similar to the Kii speaker in intent - 13th Duke of Wymbourne 22:44:19 02/06/23 (0)
        
        In Reply to: RE: My reading is that it is Bipolar posted by hahax@verizon.net on February 06, 2023 at 21:04:26
        
        Use of DSP to manipulate the radiation pattern at low frequencies.
        https://www.youtube.com/watch?v=qrl4dKK6HQM (Open in New Window)
        
        RE: My reading is that it is Bipolar - Davey 18:11:07 02/06/23 (2)
        
        In Reply to: RE: My reading is that it is Bipolar posted by 13th Duke of Wymbourne on February 06, 2023 at 17:10:28
        
        It is an interesting setup. But obviously a manipulated polar pattern that seems more like a cardioid pattern than a dipole.
        A directional objective.
        
        Of course, a dipole woofer would be symmetrical in radiation pattern. This is certainly not that.
        
        Dave.
        
        RE: My reading is that it is Bipolar - josh358 18:44:07 02/06/23 (1)
        
        In Reply to: RE: My reading is that it is Bipolar posted by Davey on February 06, 2023 at 18:11:07
        
        Curious, isn't it. A large/small driver arrangement would make sense for a cardioid (dipole + omni) or something similar. I'll have to look at the page more closely -- the polar pattern may transition with frequency.
        
        I notice that they're using the same Dayton Audio plate amp that's used on the LDW.
        
        RE: My reading is that it is Bipolar - Davey 18:53:38 02/06/23 (0)
        
        In Reply to: RE: My reading is that it is Bipolar posted by josh358 on February 06, 2023 at 18:44:07
        
        Those look to be Dayton audio speaker drivers as well.
        
        Dave.
+1 As Below Thanks for Posting! (nt) - Jonesy 11:27:19 02/06/23 (0)
nt

"I know just enough to get into trouble. But not enough to get out of it."
RE: Eminent Technology Now Has A Dipole DSP Controlled Woofer for the LFT-8C - Davey 07:51:21 02/06/23 (0)
Thanks for posting.

Dave.

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