LMS-5400 buy-in

[Ilkka]

jmcomp124 wrote:

Hi Buddy,
I just got your email and sorry I have not been that active at avs or here since I have been so busy with work. So about the PRs, you do need more washers and TC did not send me enough and I had to request more. I stopped at our local Home Depot Store (a common store in the US) and they did not have washers that size.
I requested more from Kyle and he promptly shipped me more. I think you will need a lot more than 10, so bug TC to send you more. With the way things are going with them, I don't know how lucky you will be, but make a big noise as those folks should know better. What the heck while shipping overseas why not send out more washers. I hate it, when such things happen. In the meantime, can you come up with something creative about adding more weights? It doesn't have to be washers you see !

Hi Jai,

Well here's what Kyle wrote me: "You can buy more washers at a hardware store, they should not be anymore than a buck each." I really thought that they would include washers up to 2500g as the webpage says/said. I'm not sure if I can find such washers locally.

How is the CE4000 performing?

I haven't done any thorough testing yet because that fan is definitely too loud. I need to buy a quieter one asap. I tried it briefly without the fan, and the heat sink came pretty hot already during low level listening. That's kinda strange when thinking about its efficiency? My other Class B amp (TA2400) can easily be used without a fan (not max power though).

[Ilkka]

jmcomp124 wrote:

I used to lift heavy weights and turning that thing off the cone requires some serious torque.
How did you do it? It took me a few tries before I got the sucker off. I had to replace a cone and VC that I misaliged becuase of not using a HP filter.

I just grabbed the frame and gave it a quick twist.

[Ilkka]

noah katz wrote:

Ilkka,

"Regarding those passive radiators. Mine have only single 10" spider; someone over at AVS posted pics of his PRs, and they have dual spiders?"

IMO that's a good thing.

A little bit of cone rocking (which dual spiders are meant to prevent) won't hurt anything and the lower the suspension stiffness/Fs of a PR, the better.

Here's Kyle's reply: "Don't worry about the spiders. We added a second one to the last run because we're migrating a lot of stuff to car audio where they really abuse everything. If you're using 2 PR's per active then it should never be a problem."

[jmcomp124]

Ilkka wrote:

Hi Jai,

Well here's what Kyle wrote me: "You can buy more washers at a hardware store, they should not be anymore than a buck each." I really thought that they would include washers up to 2500g as the webpage says/said. I'm not sure if I can find such washers locally.


I haven't done any thorough testing yet because that fan is definitely too loud. I need to buy a quieter one asap. I tried it briefly without the fan, and the heat sink came pretty hot already during low level listening. That's kinda strange when thinking about its efficiency? My other Class B amp (TA2400) can easily be used without a fan (not max power though).

You may want to try in the plumbing section of your local hardware store as there is a better chance of finding such large washers or nuts.
Yes, the fan is obnoxiously loud and that was the first mod I did. As I mentioned before, the SilenX fans have worked out pretty good for me. The amps did not overheat during movies but when left on overnight, at times (twice), in the morning I saw one of the amps go into protection mode (flashing red lights). It was also in the warm corner of the room.
These amps will bring out the full potential of your LMS. I would go very easy on the drivers without a HP filter. You know all the issue I had without the filter. The last thing you want is your woofer bottoming out on you. Since your tests are very controlled, I think you will find it's limitations very quickly and safely.

[Ilkka]

Comparison to 15" TC-2000, which can't be called a small woofer either. Somehow it just becomes so small next to the LMS.





The LMS next to a standard Finnish 0.5 liter beer can.

[noah katz]

"If you're using 2 PR's per active then it should never be a problem."

I stick with my contention that it doesn't matter for a PR no matter how hard you drive it.

[Scott S]

Im not sure if its been mentioned lately or not....

Are you still planning on picking up a Sound Splinter RL-p18 to test, Ilkka?

[Ilkka]

Scott S wrote:

Im not sure if its been mentioned lately or not....

Are you still planning on picking up a Sound Splinter RL-p18 to test, Ilkka?

The RL-p18" test has been postponed. At the moment I simply do not have enough time. Hopefully next spring...

[Adam321]

Too bad you didn't test the RL-p18 first. I would be more interested in that. THe LMS-5400 is unobtainable at the moment and who knows the future of TCsounds? Why drool over something that you can even get.

[Iggster1986]

Adam321 wrote:

Too bad you didn't test the RL-p18 first. I would be more interested in that. THe LMS-5400 is unobtainable at the moment and who knows the future of TCsounds? Why drool over something that you can even get.

http://www.audiopulse.com/products/s...vers/lms-ultra

patience.....

[Iggster1986]

I cant wait for the test's I am planning on buying a pair of the new ultras once the dealers have them in stock depending on test results here.

[anidabi]

Iggster1986 wrote:

http://www.audiopulse.com/products/s...vers/lms-ultra

patience.....

Hmmm... okay, so audio pulse has now almost the whole TC-Sounds lineup. I wonder how expensive the drivers will be?

[Iggster1986]

anidabi wrote:

Hmmm... okay, so audio pulse has now almost the whole TC-Sounds lineup. I wonder how expensive the drivers will be?

Depending how good you know your dealer or how good they are with prices, I would say barely more to double the price depending on those things.

[SteveCallas]

Ilkka, I believe you took a close mic, in-room THD measurement of the TC2k in free air a while back and the room didn't affect it too much. Any chance you could do the same with this driver to get an idea of what it can offer?

[Ilkka]

SteveCallas wrote:

Ilkka, I believe you took a close mic, in-room THD measurement of the TC2k in free air a while back and the room didn't affect it too much. Any chance you could do the same with this driver to get an idea of what it can offer?

Yes, I will take these in a few days. I will also add the SDX15 in the mix.

[Ilkka]

OK, here we go.

I have took some near field (around 8" distance), in-room measurements in "free air" (naturally there are some room reflections but there was no enclosure) for a few drivers I have currently in my possession. I used the same 30 second linear sine sweep as I use in my GP subwoofer tests. I tried to to match the SPL around 50-60 Hz. I started at 90 dB and went up using 5 dB steps. So THD graphs are showing curves at 90 dB, 95 dB, 100 dB, and 105 dB levels (remember 8" distance). No auto-levelling etc. was used, so the SPL is only absolute around 50-60 Hz. Everywhere else frequency response dictates the absolute SPL. Also these results are no way comparable to any GP measurement.

Don't take these measurements as the absolute truth because such in-room tests have always much greater error margin and they aren't as accurate as GP measurements.

The drivers tested were:
CSS SDX15
TC Sounds LMS-5400 18"
TC Sounds TC-2000 15" (alu cone, half-roll surround)
TC Sounds TC-2000 15" (ti cone, tall profile surround)

Let's start with the frequency responses. This graph doesn't show which driver is the most efficient because SPL's were matched. Though I can say that they all are pretty much identical when it comes to average efficiency/sensitivity. No more than ~1 dB differences.

The tall profile surround/ti cone TC2k seems to roll-off slightly faster than the regular half-roll surround/alu cone. Both of them have the greatest upper-end roll-off. The SDX15's upper-end is flatter and the frequency response extends lower but the final roll-off is steeper. The LMS-5400 has the most shallow roll-off and also the greatest upper-end output. The graph shows the frequency responses only up to 100 Hz but also above the trend is the same.



And now some distortion results. Let's start with the SDX15. It has the famous XBL^2 motor which should keep the distortion low. Indeed distortion stays quite low during "90 dB" and "95 dB" sweeps but grows pretty quickly at higher levels, especially below 20 Hz. The reason for this might be the single 8.5" spider (TC Sounds drivers have dual 10" spiders) which causes suspension-related distortion at low frequencies. The amount of distortion stays quite linear above ~20 Hz.



Then we have the TC-2000 (alu cone/half-roll surround). Distortion stays slightly lower than with the SDX15 everywhere else than in 20-60 Hz range where it forms a slight hump.



The TC-2000 with the titanium cone and tall profile surround shows pretty similar results. The hump in 20-60 Hz range is around 1% lower but nothing drastic. Could be just a slight difference in T/S data.



And then the big boy, the LMS-5400 18". I don't think much has to be said, other than the low frequency distortion during two lowest sweeps was so low that the background noise started to affect too much, so I didn't plot them. A great performance especially when noticing that it had the most output during those sweeps above ~55 Hz. In laboratory conditions (lower background noise) it could probably stay below 1% THD at all frequencies even during the "105 dB" sweep. A friendly suggestion to all LMS-5400 owners: Don't sell them.

[Iggster1986]

just wow on the lms....

[Geoff St. Germain]

Wow, the LMS is ridiculous.

[Ilkka]

Some further distortion analysis.

Here are the THD spectrum's of the SDX15, TC-2000 and LMS-5400 at 60 Hz. I have marked the first five (H2 - H6) harmonics. Other spikes are just 50 Hz hum or other background noise.

Here's a comparison between the SDX15 and LMS-5400. You can see that the LMS-5400 doesn't have much even-order harmonics. H3 (=180 Hz) is the dominant one.



Here's a comparison between the SDX15 and TC-2000. They are much closer to each other than the LMS-5400 is to either one of them.

[ISLAND1000]

I have my LMS mounted in a 6.8 cubic foot sealed box driven by a Crown XTi 4000. The amazing test results you're getting via the open air near field tests ARE easily discernable when the speaker is placed in an enclosure and driven by a suitable amp.
The response is amazingly flat or at least my listening room and the Crown amp DSP allow me to adjust it so it is . . . . at least to MY ear. The distortion is unoticeable even when the signal strength is very high and the sounds are very low. I played a 10-19 Hz sweep from the Sheffield "My Disc" 2000, track 59. It was absolutely jaw dropping to watch the titanium cone move close to it's full 38 mm Xmin and still produce controlled sonic havoc within my listening environment. I wasn't sure at first, when I cranked up the volume, whether I should stand so close to something that was that loud and violent. It shook my concrete floor and had my pants flapping like the Finnish Flag! It's truly an amazing piece of equipment.
I've been listening to (and watching) the "Discovery Channel" and have the the amp EQed through the DSP of the Crown amp. There is much subsonic music AND sounds in the background of most programing on the Discovery Channel. The program I watched first and noticed the subsonic revelations was " The Dirtiest Jobs " with Mike Rowe. It's a "must hear" and humorous too.
This LMS monster, IS a sonic marvel! Wait till you get yours in a box Ilkka. Like you suggested to those of us who own them, "Don't sell them"!

[WillyD]

Wow, wow, wow....wow. I mean...I had my suspicions concerning the LMS, but I honestly didn't think it'd test that well. And just thing, just months ago an 18" was "only" $875 shipped.

[Exocer]

Breathtaking performance for the LMS-5400, I really wished I played it smart and saved for one of them the first time around and be done with it

Too bad they're not available anymore

[jmcomp124]

I am not surprised at all.
Awesome work Ilkka. Can't wait to see the outdoor measurements. I guess the skeptics may start believing my words now about how good this woofer sounds. And for those who waited and doubted too much, too sad and for those who bought on time .