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Elite Shackster
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Re: LMS-5400 / RL-p18" buy-in

Not to be a wet blanket, but is there perhaps excessive enthusiasm considering the level at which these tests were done?

Ilkka, roughly what was the max excursion seen in this test?
The maximum peak to peak excursion wasn't more than around 10 mm, but actually that's not the point here. The point is that both the TC-2000 and the SDX15 were already starting to "struggle" at these power levels (around 15-20 watts). And you can check my latest GP session results for the TC-2000 (multiple subwoofers), and see that it isn't the worst driver there is. Far from it. The LMS-5400 is clearly superior to both TC-2000 and SDX15 when it comes to distortion. Of course it will be interesting to see what kind of difference there is when we use a few kilowatts of power. I doubt it goes smaller than these low-level tests show. :)
 
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Re: LMS-5400 / RL-p18" buy-in

I knew I should have bought 2 of these:duh: I guess the best that we can hope for now, if the MSRP is $2999, is that they'll be $1499:sick: :gah:
and if you got friends at shops about $700, I am getting a pair and showing off to people I spent $3000 on subs :bigsmile: :spend:
 

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Elite Shackster
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Re: LMS-5400 / RL-p18" buy-in

interesting you say this Steve...good to hear you change your tune. :clap: I guess it took Ilkka's measurements to prove to you why I was sackriding this driver over and over again since last year way before I did the two towers.
Oh come on Shervin, be a sport. :time-out: Neither you nor Steve had any real data to back up those assumptions and shall I say high hopes back then. Granted the specs and the marketing seemed good but as we have seen, those can't be always trusted. :)
 

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Re: LMS-5400 / RL-p18" buy-in

Oh come on Shervin, be a sport. :time-out: Neither you nor Steve had any real data to back up those assumptions and shall I say high hopes back then. Granted the specs and the marketing seemed good but as we have seen, those can't be always trusted. :)
actually, not quite bro'. Before I landed the two Ava18's, I kept the LMS5400 on the purchase button, and had several discussions, simulations (with the given T/S), comparisons with the ava18 LLT simulations, etc.............Willy can testify, as he jumped in there as well.

but all I heard back was "the ava18 is the superior driver, bang for buck", "LMS5400 doesn't seem like a good LLT driver at all...more like sealed" and "why would anyone buy this driver when you can buy 3 RL-P15's for teh same price", etc, :daydream:
http://archive2.avsforum.com/avs-vb/showthread.php?t=711678&highlight=LMS5400
http://archive2.avsforum.com/avs-vb/showthread.php?p=8465380&&#post8465380

I'm just saying..... :bigsmile:
 

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Elite Shackster
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Re: LMS-5400 / RL-p18" buy-in

actually, not quite bro'. Before I landed the two Ava18's, I kept the LMS5400 on the purchase button, and had several discussions, simulations (with the given T/S), comparisons with the ava18 LLT simulations, etc.............Willy can testify, as he jumped in there as well.

but all I heard back was "the ava18 is the superior driver, bang for buck", "LMS5400 doesn't seem like a good LLT driver at all...more like sealed" and "why would anyone buy this driver when you can buy 3 RL-P15's for teh same price", etc, :daydream:
http://archive2.avsforum.com/avs-vb/showthread.php?t=711678&highlight=LMS5400
http://archive2.avsforum.com/avs-vb/showthread.php?p=8465380&&#post8465380

I'm just saying..... :bigsmile:
No no, Sherv, you got me all wrong (well what could be expected when two non-native English speaking persons are trying to communicate over the Internet :D ).

I meant that even you didn't know that the LMS would perform this good back then. We only had the marketing talk but nothing else. So IMO it's bit unfair to say that SteveC needed my measurements to finally admit it. And because that also goes to me. :nono:

The LMS-5400 isn't still a good LLT/EBS driver. It's suited for small sealed and small ported (via passive radiators) alignments.
 

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Re: LMS-5400 / RL-p18" buy-in

ssabripo said:
interesting you say this Steve...good to hear you change your tune. I guess it took Ilkka's measurements to prove to you why I was sackriding this driver over and over again since last year way before I did the two towers.
Ilkka said:
I meant that even you didn't know that the LMS would perform this good back then. We only had the marketing talk but nothing else.
Exactly - what was the sackriding based on at the time? Flowery wording and a BL linearity chart was all they gave us, a simple FR and THD measurement like Ilkka did - which should be well, well within their capabilities - would have said tons more than even 20 pages of marketing speak.

I still don't like the parameters of this driver, as it makes it difficult to "milk" the performance out of it, but the ultra low distortion and nice FR still win me over enough to be excited (if not about this specific driver, the LMS technology). For as great as it would be in a small sealed with EQ, it would be that much better if it were suited towards a LLT. For the cost, if given the choice, I'd still take 3 Avalanche 18s to this driver, but that's not an option anymore. Now if they use this LMS technology to make an 18" driver better suited to a LLT that doesn't need its own powerplant to extract 90% of the performance.....say one that would work well in ~650 liters with a 13hz tune, and came in a bit cheaper, that would obviously be my top choice.

noah said:
Not to be a wet blanket, but is there perhaps excessive enthusiasm considering the level at which these tests were done?
It was a comparative test, so I think there is plenty of reason to be excited. It is much, much better than either of the other drivers.
 

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Re: LMS-5400 / RL-p18" buy-in

"Really?"

Yes. Titanium's advantages are high strength/mass and temperature resistance, both well beyond what is required for speakers.

"Of course it will be interesting to see what kind of difference there is when we use a few kilowatts of power. "

Yes, my point was only about the free-air THD test; even with the same motor an 18" would be expected to have lower distortion than a 15".

I did not mean to dispute that it's the top dog subwoofer driver.
 

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Re: LMS-5400 / RL-p18" buy-in

I still don't like the parameters of this driver, as it makes it difficult to "milk" the performance out of it, but the ultra low distortion and nice FR still win me over enough to be excited (if not about this specific driver, the LMS technology). For as great as it would be in a small sealed with EQ, it would be that much better if it were suited towards a LLT. For the cost, if given the choice, I'd still take 3 Avalanche 18s to this driver, but that's not an option anymore. Now if they use this LMS technology to make an 18" driver better suited to a LLT that doesn't need its own powerplant to extract 90% of the performance.....say one that would work well in ~650 liters with a 13hz tune, and came in a bit cheaper, that would obviously be my top choice.
Actually it looks pretty good in 650 liters tuned to 14hz with a 10" diameter port if you ask me:scratchhead:. You could use an 8" port but its not going to be enough if you really crank it.
 

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Elite Shackster
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Re: LMS-5400 / RL-p18" buy-in

Yes, my point was only about the free-air THD test; even with the same motor an 18" would be expected to have lower distortion than a 15".

I did not mean to dispute that it's the top dog subwoofer driver.
Yes, naturally 18" will have less excursion and therefore less distortion at the same output level, but the difference isn't this large. So the linear motor is definitely working.
 

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Re: LMS-5400 / RL-p18" buy-in

Actually it looks pretty good in 650 liters tuned to 14hz with a 10" diameter port if you ask me:scratchhead:. You could use an 8" port but its not going to be enough if you really crank it.
You are kidding right? You must be talking about the avalance, because none of the LMS looks good on 650 liter enclosure.
 

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Elite Shackster
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Re: LMS-5400 / RL-p18" buy-in

You are kidding right? You must be talking about the avalance, because none of the LMS looks good on 650 liter enclosure.
He's probably using "heavy damping" and "minor leaks" options in Unibox. With those even the LMS looks pretty good in that kind of enclosure. But they don't correlate with real world measurements. One can't stuff a ported enclosure that much because then it wouldn't work as a ported subwoofer (Helmholtz resonator) anymore.
 

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Re: LMS-5400 / RL-p18" buy-in

Ricci said:
Actually it looks pretty good in 650 liters tuned to 14hz with a 10" diameter port if you ask me. You could use an 8" port but its not going to be enough if you really crank it.
Well you wouldn't really want to use a 10" port because the length would be such that the port resonance would probably be audible. You could use a lower crossover, but then you are kind of wasting the upper frequency linear and output capabilities of this driver. I also wouldn't tune much higher than 13hz, as this driver is overflowing with capability - might as well shift some of it to the low end.

With the 8" port, you would be limiting how much output you'd be able to ask from the driver unless you don't mind chuffing. Sure, you'd be hitting reference levels before experiencing any problems, but it seems a lot of potential is wasted none the less. Also, the low end FR on such a design isn't damped enough - there is a resurgence in output belwo 20hz. On it's own it's not bad at all, maybe a db or two, but when combined with some room gain, you'd have a peaky low end.

A great driver, just not LLT friendly. It would be nice if they made one that was.
 

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Re: LMS-5400 / RL-p18" buy-in

Ilkka, perhaps a silly question, but could you hear any sonic differences between the drivers just from testing them in free air with a FR sweep? When it comes to real material, I wonder if the difference would even manifest itself, as the other two drivers stayed below 5% at the same levels in the audible range, which isn't shabby by any means except when compared to the LMS. Seeing as the distortion on the other drivers only starts rising in the subsonic range, and the subsonic range is mostly limited to movie sound effects, I wonder how much of a difference it would make.

Don't get me wrong though, this driver is clearly superior, and it definitely gets the nod.
 
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Re: LMS-5400 / RL-p18" buy-in

Regarding those passive radiators. Mine have only single 10" spider; someone over at AVS posted pics of his PRs, and they have dual spiders? :hissyfit:
For ease of reference, I'll post the pictures here also:
 

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Re: LMS-5400 / RL-p18" buy-in

No I actually wasn't kidding. It doesn't look that bad. Yes it gets a little peaky around 13-15hz, but it's only 2db's. Whats wrong with using a little EQ? The 10inch vent would have a port resonance of 172hz, kind of low, yes, but i've seen worse. Of course this is not what it was intended for, and the response does look like **** compared to a nice 400L enclosure. 13-200hz response within 3.5dbs is far from terrible though.Maybe my parameters are off slightly. Of course this is all just simulation anyway, and not real world measurement.

NO I would not actually use an LMS like that.
 

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Re: LMS-5400 / RL-p18" buy-in

"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.
YAH RIGHT, lok what i did to mine, and they where the oem10 passives with extra strong cones. dual passive enclosure with a single OEM10 both passives went. took very little figer presure to turn the cone out like that afterwords

 

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Elite Shackster
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Re: LMS-5400 / RL-p18" buy-in

No I actually wasn't kidding. It doesn't look that bad. Yes it gets a little peaky around 13-15hz, but it's only 2db's.
2 dB? Unibox shows closer to 5-6 dB when compared to proper LLT.


Whats wrong with using a little EQ?
Most EQs can't equalize frequencies below 20 Hz.
 

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Elite Shackster
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Re: LMS-5400 / RL-p18" buy-in

Ilkka, perhaps a silly question, but could you hear any sonic differences between the drivers just from testing them in free air with a FR sweep? When it comes to real material, I wonder if the difference would even manifest itself, as the other two drivers stayed below 5% at the same levels in the audible range, which isn't shabby by any means except when compared to the LMS. Seeing as the distortion on the other drivers only starts rising in the subsonic range, and the subsonic range is mostly limited to movie sound effects, I wonder how much of a difference it would make.

Don't get me wrong though, this driver is clearly superior, and it definitely gets the nod.
Not a silly question at all, Steve. Yes, I could hear a difference between the drivers with just a sine sweep. The LMS sounds cleaner/purer than the TC2k or the SDX15. Especially during the two highest sweeps.

But you shouldn't look at the absolute distortion ("stayed below 5%") because that's just a random value, so to speak. This kind of near field free-air testing doesn't really reflect any kind of real world situation (minus dipole subwoofers). It's only good for comparison purposes.

The LMS-5400 18" seems to have around 6 dB more output than the TC-2000 15" while keeping the same distortion level. Typically 18" will gain around 2-3 dB over 15", so the LMS seems to be at least 3-4 dB better than a typical 18" LGLC (and I would say XBL^2, too) subwoofer when it comes to harmonic distortion. Not quite the full 6 dB TC Sounds promised, but still quite a lot. Of course harmonic distortion isn't everything. The free-air frequency response looks really good due to total lack of typical inductance hump (actually looks like a small notch instead). That should work really well when put in an enclosure. I doubt much EQ will be needed to bring it nice and smooth. So quite different than the sealed Tumult or the TC-2000s I measured last time. :thumbsdown: Then there is also power compression. The massive 4" VC with titanium former should perform really well when some real men power will be utilised. Then we will know more about the real difference to "weaker" drivers.

But naturally the LMS-5400 isn't really for those looking for the best bang for teh buck...but I guess that's pretty obvious.
 
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