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*sub pics courtesy of JoeHemi57*











I picked up this sub brand new for $220 shipped on ebay. It's quite a heavy and well built driver. I like the cooling fins over the magnet and the huge pole vent. The push terminals are also solid. With such a large vent however, it would have been nice to see a mesh screen to prevent debris or polyfill from getting into the motor. The quick change assembly is also a handy feature, allowing you to remove the motor from the voice coil/chassis assembly in a matter of minutes.... essentially the time it takes to unscrew 4 bolts.

This sub is also my first LMT driver, and I was quite impressed with the test results. For those that are new to LMT, it uses a variable thickness voice coil. This technique has a significant advantage in providing long stroke, however it seems to be more susceptible to manufacturing variance as evidenced by the skewed BL curve. Another downside is the low sensitivity (~81db) and high q... which isn't necessarily a bad thing if you need a dipole or IB woofer with an f3 in the 20ish hz range.

Another thing to note is the exceptional LE linearity and low inductance for a driver with such a large voice coil. Looking at the distortion plot, you can see that at almost all power levels the suspension based distortion is a good deal higher than bl or inductance related distortion... indicating quite a remarkable motor design.

Overall, I like this driver. It provides a huge linear stroke of almost 40mm 1 way (although there's quite a bit of mechanical noise at this point) and excellent powerhandling for a modest $200... just make sure you can deal with the huge box requirements (over 4cft sealed for a qtc of .707) and low efficiency ~81db. Subjectively, I found the driver to be quite a bit bottom heavy and boomy in my car, but nothing an EQ couldn't fix (although that ruined the already poor efficiency even more)... still it's singing happily away in my car with a modest 400 watt amp.
 

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oops nevermind, found one, 40mm one way!!!?!? Good lord. Too bad about the huge box requirements, I have 1100 watts to spare tho...
 

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some guy over at caraudio wanted the scan of the manual

so I thought id post it in case someone else wanted to read it

http://www.yousendit.com/transfer.php?action=download&ufid=16D5426C54078D19

youve only got 7 days to get it though from 7/18

last page is upside down


sorry about that, and the 10 7/8 is the jasper jig hole to use to make the cutout using a 1/2" diameter bit as a reference

also on the side of the box the overall diameter is 12.6", and the magnet diameter is 8-5/8", and total depth (from bottom of basket to top of gasket is 8".

and for reference here are the tc lms-4000 specs

http://www.tcsounds.com/lms4000.htm#specs
 

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Ya, where did you get a klippel? Very very nice!

The graph generally looks like this, which is fairly linear



FYI, Normal Bl curves look like this:



Here is the Eclipse SW8200 linear coil next to the Eclipse non pro Titanium quad coil



I really like the new eclipse and probably ran it on a klippel against 10-15 different subwoofers including a W7, it continually killed everything for low distortion.

In your case, take a look at your suspension, it probably sags just a bit downward. If thats the case, it will throw the graph off a bit (its not a big deal!). The early versions of the eclipse had that problem but it probably won't be very audible, only measurable with a Klipppel as shown. Beside, you'll rarely hit 40cm one way and if you do, it’s still going sound a lot better than anything else. It does hold a true 6dB advantage over the same motor w/o the linear upgrade. The downside is the higher Q so it will not work in a ported alignment and the sensitivity is low too. But for the money, it’s still a far better sounding driver than everything that can hang with it for excursion and output.

Switching gears...

The new LMS-4100 and 5400 were designed to have lower Q and higher sensitivity. The LMS-5400 pulls a Q of nearly 0.2, and has much longer coil. We rate is about 36-38mm xmax where as we rate the SW8200 at about 30mm. You have shown that it can go to 40mm at about 70%Bl which is generally accepted to be the Xmax figure. The LMS-5400 will probably push 50-55mm at 70% BL and probably edge out the 06 XXX outright with about 4dB higher sensitivity.
 

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Discussion Starter #8
Awesome, thanks for sharing!

Off-topic... do you have any info on those neo motors? They look amazing.
 

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npdang said:
Awesome, thanks for sharing!

Off-topic... do you have any info on those neo motors? They look amazing.

Not really other than price.

And they are not cheap, the neo is VERY expensive. That’s why it's rarely used.

It’s a 7" wide neo ring for a 3" dual linear voice coil on a titanium former that’s about 3.2" tall wading height. If we didn’t use a linear coil the Q would be low enough to use the subwoofer as a midrange driver!
 

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does that use a tc-9 motor? i can kinda see it throught the fins.... that thing seems really popular with tC no?
 

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Kyle said:
???for you???
just wondering what you guys are recommending for enclosures?? I modeled mine at 3.5 cu ft sealed 9bass box pro), so IM more inclined to drop in the house. since they sound so damn good (HY temp box, low power)

Id love to use em in the car, but I dont want to lose spl/and tonality by choking em too much (ive only got 2 cu ft net sealed)
 

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newtitan said:
just wondering what you guys are recommending for enclosures?? I modeled mine at 3.5 cu ft sealed 9bass box pro), so IM more inclined to drop in the house. since they sound so damn good (HY temp box, low power)

Id love to use em in the car, but I dont want to lose spl/and tonality by choking em too much (ive only got 2 cu ft net sealed)

You use these as a guide

http://www.tcsounds.com/lms4000.htm#diy
 

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What's with the spider on the SW8200? The Cms(x) plot is extremely nonlinear for a transducer with such a high advertised Xmax or is the surround roll too small? The nonlinear parameter method for determining Xmax is typically, Bl(+/-Xmax) = 0.70Bl(0) and Cms(+/-Xmax) = 0.70Cms(0), from Klippel. I personaly prefer Bl(+/-Xmax) = 0.75Bl(0) and Cms(+/-Xmax) = 0.75Cms(0) for subwoofers and a higher standard for mid and high frequency transducers, although displacement are much smaller. Now based on the nonlinear parameter plot Cms(x) from the KLIPPEL DA and using 70% of the small signal parameter value, http://diymobileaudio.com/pics/eclipsesw8200/cms.JPG, Xmax = 25 mm; -Xmax = -18 mm. Then assuming the voice coil was not positioned correctly during assembly, (18 + 25) / 2 = +/- 21.5 mm (43 mm peak to peak stroke). Sure the cone can go farther but distortion is high, http://diymobileaudio.com/pics/eclipsesw8200/distortion.JPG. The conditions stated above for Xmax will keep distortion closer to a more reasonable 10% related to the transducer's suspension.

Anybody having torn spider failures? :confused:
 

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I want to try one of these out in the car but I am scared about the horror stories I have seen about the cone cracking at the surround. I also remember reading about elcipse having problems with a particular buildhouse. On the upside there are supposed to be a newer batch of these lmt drivers but here are my questions.

1. How can you tell this is from the newer batch?
2. Considering the enormous one way stroke and soft parts used is it rational to believe all of these subs would fail mechanically?
3. So in the car it need over 3 cubes sealed for proper response? Thats crazy and how is eclipse getting away with recommending a cube or so.

I would really like to try one of these since it seems like the cheapest ticket of entry into the world of LMT.
 

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I want to try one of these out in the car but I am scared about the horror stories I have seen about the cone cracking at the surround.
Well that sounds like the surround is pulling up. The cone is cracking, why? Exceesive stress at the surround to cone termination.

:eek:
 

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