# JL Audio 12w6v2



## ErinH (Feb 14, 2007)

*JL Audio 12w6v2:*
JL Audio 12W6v2 Subwoofers - Car Audio Subwoofers


*Klippel Test Settings:*
Changed to be more flexible for subwoofer testing (this will always be replicated in future subwoofer tests):
Blmin set to 70%
Cmin set to 50%
Zmin set to 17%
Doppler Distortion set to 10%

Data attached via PDF.


- Erin


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## Brian Steele (Jun 1, 2007)

Curious results...


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## cvjoint (Mar 10, 2006)

Tests as expected inductance wise (bad) and suspension wise (good). The Bl sure looks funky. Highly asymmetrical and limiting hardcore on the rear travel. That was unexpected.


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## DS-21 (Apr 16, 2005)

Looks like the motor was designed more to keep people from blowing them up than to provide extremely linear performance.

Probably not the worst engineering compromise for a car audio subwoofer maker, to be honest. Considering that these are sold largely through shops of often questionable knowledge/ability and not focused on the more sound-driven DIY market, at least.


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## cvjoint (Mar 10, 2006)

I know everyone that gets one of these claims they chose it over the W7 for the sound quality difference. I bet the W7 tests better, I mean it kinda has to looking at this one.


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## Brian Steele (Jun 1, 2007)

cvjoint said:


> I know everyone that gets one of these claims they chose it over the W7 for the sound quality difference. I bet the W7 tests better, I mean it kinda has to looking at this one.



A couple things come to mind:

1. There's an error in the measurement process and the results don't reflect the true characteristics of the 12W6v2
2. The results are correct, but there's a problem with this specific 12W6v2
3. The results are correct, and reflect the general characteristics of a 12W6v2.

Now, have a look at the following link: JL Audio 12W6v2-D4 Subwoofer Review - Subwoofer Reviews - Car Audio and Electronics. The 12W6v2 was previously Klippel'd in 2004 by Red Rock Acoustics and found to have a BL curve that was "about as close to perfection you are going to get this side of Nirvana". 

So, I'm going to suggest that chances are that either option (1) or option (2) applies here. 

We can eliminate option (1) by comparing one of the Klippel measurements against another that was recently performed on the same driver by another company. With that in mind, perhaps Jacob Fuller can volunteer that Sundown SA-12 driver he had recently Klippel'd by Red Rock Acoustics for testing via the DIYMA Klippel. If the results are very similar, if not identical, then that will reduce the possibility that there's something wrong with the measurement process or the equipment.


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## ErinH (Feb 14, 2007)

Well, to put it simply, the klippel measurement system is incredibly easy. if there's a fault, it's in the hardware.
You do a sweep, get Bl, Mms, and Re. My specs are similar to those of the one you linked. Not drastic differences:
My values: Bl = 19.4, Mms = 176g, Re = 6.2 ohm.
Their values: Bl = 20.4, Mms = 181g, Re = 6.58 ohm.
The minimum parameters used were in line with what other companies are doing for subwoofers.
The stand is sturdy; as long as the prongs don't move the measurement is constant.
I do 3 rounds of testing to verify the results aren't erroneous (at least, not in the repeatability sense).


I understand placing weight in to the published spec linked above. I also would advise you to use caution on their measurements just as much as you would mine. They may be more correct or they may not. 
If someone wants to send me a 2nd 12w6v2, I'd be happy to test it.


Edit:
For the life of me, I'm not seeing the Bl curve they say is "pictured below" in that link. 
Instead of just saying it, I'd like to see the results myself.


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## cvjoint (Mar 10, 2006)

Brian Steele said:


> A couple things come to mind:
> 
> 1. There's an error in the measurement process and the results don't reflect the true characteristics of the 12W6v2
> 2. The results are correct, but there's a problem with this specific 12W6v2
> ...


1. I see what you are saying, basically does the laser make a difference. I think RR Acoustics would be using one. I'd say in general the results make a lot of sense, but I see your worry here, it's justified.

2. Not very likely. Suspension damage is likely. BL? Maybe if it was a 10 year old sub. 

3. My best guess.


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## Brian Steele (Jun 1, 2007)

bikinpunk said:


> I understand placing weight in to the published spec linked above. I also would advise you to use caution on their measurements just as much as you would mine.


Oh, I wasn't questioning anyone's measurements, particularly yours. I suspect that, even though the process might be "easy" as you say, you've probably put in a LOT of time to ensure that the possibility of errors being introduced is minimized.

What I'm looking at here is simply looking at the various possibilities that may have led to the results being what they were, and what could be done to eliminate some of possibilities.



bikinpunk said:


> If someone wants to send me a 2nd 12w6v2, I'd be happy to test it.


That's another great way of eliminating one of the possibilities - whether or not what you measured is indicative of the 12W6v2's general characteristics.

If we could get hold of the same SA-12 that was justed tested by Red Rock Acoustics and subject it to measurement on the DIYMA Klippel, we can eliminate the possibility that something may not be right in the measurement process or the equipment itself (by testing the same driver that was previously tested, we will also eliminate the impact of manufacturing variance, like centering the voice coil).


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## Brian Steele (Jun 1, 2007)

bikinpunk said:


> For the life of me, I'm not seeing the Bl curve they say is "pictured below" in that link.
> Instead of just saying it, I'd like to see the results myself.


This is mentioned at the top of the article: "some of the figures referred to below could not be recovered. We'll work on restoring the rest of this article as soon as we can." Evidently the article dates back to 2004.

Maybe it was printed article. Perhaps it's time to check the archives. I wasn't a big CA&E fan (I preferred CSR), but I do have quite a bit of their published magazines...


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## sundownz (Apr 13, 2007)

Brian Steele said:


> If we could get hold of the same SA-12 that was justed tested by Red Rock Acoustics and subject it to measurement on the DIYMA Klippel, we can eliminate the possibility that something may not be right in the measurement process or the equipment itself (by testing the same driver that was previously tested, we will also eliminate the impact of manufacturing variance, like centering the voice coil).


It is still at Red Rock at the moment -- I was going to have Patrick abuse it thermally to failure but I could always do that at a later time with a different unit if it could resolve some debate over here.


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## Brian Steele (Jun 1, 2007)

sundownz said:


> It is still at Red Rock at the moment -- I was going to have Patrick abuse it thermally to failure but I could always do that at a later time with a different unit if it could resolve some debate over here.


I think this is an excellent opportunity that shouldn't be passed over.


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## Eric Stevens (Dec 29, 2007)

I can tell you that Matt measured a JL 10W6 V2 and it measures much better than what you show here for the 12. It was very linear and symmetrical in both Bl and compliance. The sub that was tested was a couple of years old as well, not something new out of a box.

Eric


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## msmith (Nov 27, 2007)

As a couple of others have theorized, I'm pretty sure that something is funky with the driver that was tested, or with the test (or maybe both to some extent). A 12W6v2 in good working condition tests waaay better than that, and this has been confirmed independently. 

I will show these test results to our engineers on Monday and maybe they can help figure out what might be going on. 

TTY tomorrow. 

Manville Smith
JL Audio, Inc.


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## Brian Steele (Jun 1, 2007)

cvjoint said:


> Suspension damage is likely.


This might be worth exploring. Perhaps the spider and surround on the tested driver should be examined for any rips or other noticeable damage.


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## cvjoint (Mar 10, 2006)

Lots of good things going on here. Tuned in.


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## ErinH (Feb 14, 2007)

msmith said:


> As a couple of others have theorized, I'm pretty sure that something is funky with the driver that was tested, or with the test (or maybe both to some extent). A 12W6v2 in good working condition tests waaay better than that, and this has been confirmed independently.
> 
> I will show these test results to our engineers on Monday and maybe they can help figure out what might be going on.
> 
> ...


Sounds great, Manville!


I really appreciate all the feedback. 


I'd certainly love to know if something's up with the hardware. Ant's sent it off twice to be repaired so I'd hope nothing's wrong there.
The stand I built holds the driver quite well and I've isolated the terminal clips to make sure they don't move. The Klippel machine is pretty simple to operate so user error truly is not of concern to me. 
I tested this particular driver 5 times because the first result was the same as the last. The same curve on each result. Which is in stark contrast (apparently) to what I should be getting.
I, too, would love to get to the bottom of this. As a tester, my top priority is making sure that what I post is accurate. 
I appreciate your input in to this matter. You were actually a day ahead of me... an email was going out to to you today once I got to work. 

Manville, if you or your team would like to reach me personally feel free to contact me via email and I'll give you a call:
hardisj @ gmail.com



- Erin


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## ErinH (Feb 14, 2007)

sundownz said:


> It is still at Red Rock at the moment -- I was going to have Patrick abuse it thermally to failure but I could always do that at a later time with a different unit if it could resolve some debate over here.


I'd be all for that. Another way of certifying what I get would really be great.



cvjoint said:


> Lots of good things going on here. Tuned in.





cajunner said:


> this is the DIYMA I knew was hidden in all those "what sub do I go with?" threads..


Yep.

You'd think I'd be in "oh ****" mode, but I'm in "HELL YES!" mode right now. 
I'm excited to see this forum get back to what it once used to be. 

Now, let's see what's going on here...


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## ErinH (Feb 14, 2007)

Brian Steele said:


> This might be worth exploring. Perhaps the spider and surround on the tested driver should be examined for any rips or other noticeable damage.


The driver was lent to me by someone local. AFAIK, the driver has been taken well care of, though I truthfully don't know it's history. It looks to be in great shape. I think they bought it with the prowedge box and didn't appear to have ever been removed from that enclosure until I took it out myself.


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## Brian Steele (Jun 1, 2007)

bikinpunk said:


> It looks to be in great shape.


Try feeding it a >10 Hz signal that noticeably exercises the suspension. If something's wrong with it, perhaps it will be more noticeable when the cone's actually moving.


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## ErinH (Feb 14, 2007)

When it was under test, I went upstairs a few times to watch it. The more constrained tests (distortion kept @ 10% by parameters) looked fine. Amp was not clipping, all looked well. Driver was moving well.
Went back up after I let "loose" on it by relaxing the parameters to what you see posted above and all looked well. Driver didn't seem to be killing itself but it was certainly moving. 

When I do these kind of tests I start at low power and watch it. I do each test at least 3 times (5 times in this case) and I keep an eye on the driver when it gets to the high(er) power portion of the test.


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## ErinH (Feb 14, 2007)

FWIW, I contacted Red Rocks. They're comment pane is very short so I couldn't give them much information as to why I was contacting them. I'm hoping maybe they might be able to provide some insight out of the goodness of their hearts, but I won't hold my breath, seeing as how they might view me as a "competitor" (though, certainly not making any money off this stuff...).


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## sundownz (Apr 13, 2007)

I'll see if Patrick @ Red Rock can send it straight to you -- where should I have him ship the SA-12 ?


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## ErinH (Feb 14, 2007)

I sent you a PM with my address.

Thanks


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## msmith (Nov 27, 2007)

This online posting of the CA&E article has the 12W6v2 Klippel BL curve measured by Redrock Acoustics



Uploaded with ImageShack.us

You can see the whole article here:

JL Audio 12W6v2-D4


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## MiniVanMan (Jun 28, 2005)

sundownz said:


> I'll see if Patrick @ Red Rock can send it straight to you -- where should I have him ship the SA-12 ?


I still have the results from the SA-12 that I tested if that helps. Give me your okay and I'll send them over to Erin.

My results differ from Red Rocks in almost the same way as Erin's differ from theirs. So that begs the question, does a laser attachment really make that big of a difference?

Then again, my tests were based on pounding the snot out of the sub, and I was really only concerned about generating the temperature and distortion reports.


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## MiniVanMan (Jun 28, 2005)

msmith said:


> This online posting of the CA&E article has the 12W6v2 Klippel BL curve measured by Redrock Acoustics
> 
> 
> 
> ...


That curve looks very much like the Erin's. Erin's looks a bit more exaggerated, but it follows the same pattern.


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## ErinH (Feb 14, 2007)

Patrick @ Red Rock has contacted me and offered some help. If we come to any substantial conclusions, I'll report back.


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## SSSnake (Mar 8, 2007)

It appears to me that Erin's measurements were taken in series while Red Rocks were parallel (just from looking at the Bl curve). Can someone confirm this?

Erin,

This is likely a stupid question so I will apologize ahead of time. What limits the excursion vs Bl plot? I had ASSUMED in the past this was limited by % reduction in Bl (in this case 70%) barring some other limiting factor (protection related). In this case it appears you set the test up for Bl variations up to 70% but the graph looks like it only runs to 80%. The Red Rocks plots looks like about 60% of Bl. I couldn't readily see any other protection issues coming into play on your measurements... Again likely something I have just completely missed but I wanted to ask the question (particularly given the questions surrounding this set of measurements).

Thanks

Charles


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## MiniVanMan (Jun 28, 2005)

SSSnake said:


> It appears to me that Erin's measurements were taken in series while Red Rocks were parallel (just from looking at the Bl curve). Can someone confirm this?
> 
> Erin,
> 
> ...


I noticed the same thing. Uncompress Erin's graph laterally, and it'll look a lot more like Red Rock's graph.


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## cvjoint (Mar 10, 2006)

Xmax based on 82% BL is limited on the backward stroke in both graphs. It amounts to 11mm in Erin's test and about 12.5mm in RRAs case. The asymmetry has the same pattern but it's just a tad more pronounced in Erin's tests. Not a big difference. Maybe the motor strength dropped a bit since it was a used sub? Now how come in these tests the BL is 19 vs 10 in the tests just provided?


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## SSSnake (Mar 8, 2007)

CV,

For the difference in Bl I think it is likely series vs parallel.

I probably worded that wrong but Erin's graph doesn't go as high in terms of percentage decrease in Bl - roughly 80% on Erin's (I expected 70% based upon test setup paramters) and 60% on Red Rocks. My real question is why did it stop at roughly 80% not 70%?

Charles


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## ErinH (Feb 14, 2007)

Patrick has gotten back to me. He's gonna school me. I'm pumped! 


Charles, all I know right now is that all the parameters seem to be limited at the same point. I'm not seeing the limiting factor; either in the graphs or in the non-linear parameters table provided in the results. All limit @ ">11.5mm".

Let me chat with Patrick and see what he has to say. I'll come back. I'm learning, too. 

Thanks for the input, guys.


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## cvjoint (Mar 10, 2006)

bikinpunk said:


> Patrick has gotten back to me. He's gonna school me. I'm pumped!
> 
> 
> Charles, all I know right now is that all the parameters seem to be limited at the same point. I'm not seeing the limiting factor; either in the graphs or in the non-linear parameters table provided in the results. All limit @ ">11.5mm".
> ...


13.5 BL corresponds to 70% BL. That is the limit you gave it, that's where it stopped. At 70% BL it's still at 14mm, 2.5m shy of the manufacturer's spec. Since the other test has a bit more BL and uses a newer sub it could be just that. 

I too would expect the Klippel to tell you which one is the limiting factor. I mean we can figure it out but why does it say > x for all of them? Not sure.

The VC arrangement would explain the BL. Haven't used dual coils in a few years. :blush:


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## ErinH (Feb 14, 2007)

On some tests where Cms has been the limiting factor, it's outright said it. If I change the parameters around, I can see the limits change in the nonlinear parameters table (I toy with this stuff just to see what happens). 


Again, I'll chime back in once I talk with Patrick. Dude's been extremely helpful.


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## ErinH (Feb 14, 2007)

Just had a 30 minute convo with Patrick. Great guy. Great info.

I took a lot of notes. Will try to cover them at a later time.

The gist of the convo, though was:

I need the laser to get a more accurate curve
I need to relax the protection parameters (not the thresholds) to get a more meaningful curve fit

He and I discussed the 10 and 20% distortion threshold limits. Was GREAT hearing it from the horses mouth (he came up with the 20% limits that mfg's follow now). He also highly recommends that we get the laser. He's going to write up an email for me to fwd to Ant regarding this matter and I'll post up what he said. He's a lurker here now but maybe I can get him involved and to school us all a bit.


Seriously, I feel MUCH more comfortable about all of this now. Dude was great to talk to. I learned more in the last 30 minutes than I had the previous month. All I needed was a resource to answer the questions no one else has been able to. 

He's going to even provide me with data to post up here until we can hash out some of these details regarding the laser and other measurements and said he'd be happy to review my future data as well as provide some analysis. 

In the meantime, I'm going to hold off on further testing and will also consider pulling the data I've provided down and retesting the drivers as soon as I can.

Feel free to provide your $.02. 

- Erin



Patrick,
Thank you so much, man.


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## BuickGN (May 29, 2009)

If this isn't resolved and no one else steps up, I'll ship mine over to you when I get back from my cruise next week.

Just curious since this seems to be the thread to ask, what's the xsus or xmech of the 12W6? When in IB before I added a subsonic, it had a stupid amount of excursion. Just wondering what the limit is before it can do no more or it destroys itself.

I love these types of discussions.


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## Redrock (Jun 6, 2011)

Hello all!
Just wanted to say you never stop learning. I have tested literally thousands of speakers with the Klippel - everyone with the laser and I made the (incorrect) assumption it was required for LSI testing. I just ran tests both with and without and they are pretty much identical. Klippel gives you excursion data, but it derives it from the mass/current/voltage data and a curve fit. From this it knows acceleration and excursion. I will do this a few more times to see if I can find divergence. I will also send a quick note to Wolfgang and see what he says. The good new is that your Klippel system will give you the non-linear data you want to see. 
I will also be happy to help make sense of the data as you take it. 
Patrick


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## ErinH (Feb 14, 2007)

Patrick, glad to see you signed up! 


Everyone else, here's the skinny....
I now owe Patrick about $48 for used cell phone minutes today. Well, not really, but he's been great in helping me out. I think we've managed to talk for a bit over an hour in two different sessions today. 
I've tested the JL again multiple ways. I've gotten closer to data that makes sense, however, Patrick (and I) are concerned that the DUT may be defective. Preliminary 2 ohm tests look to show this. I'm going to re-test at 2ohm fully tomorrow to see what I get. The T/S parameters I just got match his very closely so we'll see how the Klippel testing goes. I may have to find another sample (Manville, care to PM/email me to discuss possible replacement?), though.


In the meantime, Patrick has offered up his database for me to peruse and pick out driver data to post up here. Hopefully I'll be able to do that within a few days. The mounds of data he has at his disposal should easily hold us over a few weeks.
I think we should all give him a huge THANK YOU for taking time out of his busy schedule to help me out. And, while we're at it, we need to send flowers to my wife who is about to divorce me, take the baby and dogs, and leave me with the mortgage.  


Regarding the data I've posted so far, I may (or may not) pull it all (the previous 4 rounds of test data) and re-test them all given the new information Patrick has been nice enough to share with me. 
I think it's only fair. Feel free to chime in regarding if it should be deleted or simply added to with a disclaimer... my only reason for not deleting it is to possibly show the differences in how the tests parameters can affect the data. 

Side note: Patrick has the aurilization module and from what he told me earlier, that thing sounds (no pun intended) awesome!
http://www.klippel.de/measurements/nonlinear-distortion/auralization.html



- Erin


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## ErinH (Feb 14, 2007)

Got a JL tech helping as well. 
Welcome to Klippel school.....


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## cvjoint (Mar 10, 2006)

bikinpunk said:


> In the meantime, Patrick has offered up his database for me to peruse and pick out driver data to post up here. Hopefully I'll be able to do that within a few days. The mounds of data he has at his disposal should easily hold us over a few weeks.


What? Really? That is fantastic! epper:

Getting one of these tests is like Christmas, and well we've had about a couple per Christmas too between the Npdang days and Erin. This is much appreciated. 

If every manufacturer use the whole host of know-how Red Rock Acoustics has at their disposal we'd be bathing in hi end drivers. Patrick :thumbsup:

You know how I feel about deleting things. Putting a disclaimer as to why you think the results might be questionable in the first post would be very professional. Newer tests can be added on if they are more accurate and linked properly with a note.

Audiophilia should be a disease. I know I spend far too much time on this board and I don't do a fraction of the work you do. Prioritize accordingly, I won't be a hater.


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## sundownz (Apr 13, 2007)

Welcome Patrick !


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## SSSnake (Mar 8, 2007)

CV,

Reference your comment:



> 13.5 BL corresponds to 70% BL. That is the limit you gave it, that's where it stopped. At 70% BL it's still at 14mm, 2.5m shy of the manufacturer's spec. Since the other test has a bit more BL and uses a newer sub it could be just that.


I thought the black trace depicted the range where Bl was still within limits and the red trace indicated where the driver could operate before mechanical damage. In that case the Bl never dipped below roughly 16 (or 80% of Bl maximum). The other side of the curve stops at roughly 19 (which I really don't understand). I assume that some other thresholds have been exceeded but can't tell what they are or why.

I see you are getting the 13.5 or 14Bl from the red trace but the table indicates "XBl @ Bl min =70%" at 11mm which ties back to my roughly 16Bl value. 

As previously mentioned I may be interpreting this competely wrong and if so I apologize. Please educate me 

Patrick,

Thanks for becoming active in this fourm and welcome to the fun!

Erin,

Get off you butt and get this done! Besides you never know wife version 2.0 might be an upgrade.  JK - The reason my installs take multiple years has more to do with WAF than it does anything else.


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## cvjoint (Mar 10, 2006)

The Klippel doesn't know damage limit or xmech if you may. That's why you have to set protection limits. In this case the protection was set at 70% BL and that's how low it went. Linear BL is only down to 82% and that coincides with the start of the red. The end of the red would be damage but no woofer gets tested to 100% BL, CMS etc. The other side stops at 19 because by then the rearstroke is way out of linear range. What's the point of finding one side bl? I don't think the Klippel test one side at a time. That's my understanding of it.

Just looking at the graph 11mm corresponds to roughly 16BL. 16/19.3=.82 or 82% of BL. It is not 70%. The table reads >11mm which could be the 13.5 BL or 14mm.


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## ErinH (Feb 14, 2007)

Well, it's my understanding that the protection parameters are what drive the limits of the test and the thresholds are what give you the values of xmax @ X parameter.

So, in the latest case, I am using 25% Bl and Cms for protection, and the thresholds of 70 and 50% are what limit the actual xmax values and what the test data is based on.

Patrick will have to verify, though. I'm still learning as I go.


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## DS-21 (Apr 16, 2005)

Wow, this thread got interesting (in the educational, not Chinese, sense) real fast!


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## cvjoint (Mar 10, 2006)

bikinpunk said:


> Well, it's my understanding that the protection parameters are what drive the limits of the test and the thresholds are what give you the values of xmax @ X parameter.
> 
> So, in the latest case, I am using 25% Bl and Cms for protection, and the thresholds of 70 and 50% are what limit the actual xmax values and what the test data is based on.
> 
> Patrick will have to verify, though. I'm still learning as I go.


Hmm, I see you changed the xmax thresholds for the sub testing. Then why did it stop so early? It was not reaching any of the limits you set. That's why we have the ">" and no "=". We don't know the limiting factor when the testing stopped. I'm confused now.


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## ErinH (Feb 14, 2007)

There are two sets of tabs:
Protection
Threshold

They are not necessarily related. I'll try to explain later.

For now, here's a video of the testing... might be cool to see it in action:
YouTube - ‪JL Audio Testing‬‏


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## SSSnake (Mar 8, 2007)

Video sux! No magic smoke  but seriously man you need to cut down on the caffeine. I almost got sea sick watching the video.

I'll refrain from asking anymore questions until you get through with the discussion with Patrick.


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## ErinH (Feb 14, 2007)

I hate you. 

Besides, Todd's the caffeinated one.


Patrick may be the best to answer these questions. I don't want to put any bad info out there.


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## ErinH (Feb 14, 2007)

just an update...

I've now tested this woofer 15 ways from Sunday all the while talking with Patrick and a JL Engineer. The results keep trending in the same direction and the more the tests are done, the more I'm convinced that this is a bad woofer (given the talks I've had with Patrick). 

That's all for now...


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## BuickGN (May 29, 2009)

bikinpunk said:


> just an update...
> 
> I've now tested this woofer 15 ways from Sunday all the while talking with Patrick and a JL Engineer. The results keep trending in the same direction and the more the tests are done, the more I'm convinced that this is a bad woofer (given the talks I've had with Patrick).
> 
> That's all for now...


The below is still available..... And also, any idea what xsus or xmech might be?



BuickGN said:


> If this isn't resolved and no one else steps up, I'll ship mine over to you when I get back from my cruise next week.
> 
> Just curious since this seems to be the thread to ask, what's the xsus or xmech of the 12W6? When in IB before I added a subsonic, it had a stupid amount of excursion. Just wondering what the limit is before it can do no more or it destroys itself.
> 
> I love these types of discussions.


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## t3sn4f2 (Jan 3, 2007)

bikinpunk said:


> just an update...
> 
> I've now tested this woofer 15 ways from Sunday all the while talking with Patrick and a JL Engineer. The results keep trending in the same direction and the more the tests are done, the more I'm convinced that this is a bad woofer (given the talks I've had with Patrick).
> 
> That's all for now...


You need an amp with more SQ and a stand with double layers of CLD.


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## myhikingboots (Oct 28, 2010)

Okay will someone tell me if I should buy this sub or not. Damn techies!


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## BuickGN (May 29, 2009)

myhikingboots said:


> Okay will someone tell me if I should buy this sub or not. Damn techies!


You should definitely buy this sub. It's one of the best I've ever heard.

Edit: And I literally forgot that I had one for sale when I wrote that lol.


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## ErinH (Feb 14, 2007)

I tell you what... this sucker has one hell of a suspension system. If you look at the video, that's 200w _free-air_ and it's not jumping around or moving out of the gap.
The woofer I have just seems to have an issue with the alignment. Hopefully we can get something worked out and have more credible (for lack of a better word) data up sometime soon.


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## sundownz (Apr 13, 2007)

Did the SA-12 show up yet as a comparison ?


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## ErinH (Feb 14, 2007)

Not yet. I'll let you know when it does, though. Thanks for helping us out.


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## ErinH (Feb 14, 2007)

Alright guys, after numerous rounds of testing, I've finally posted up the latest data which has been given Patrick's blessing. At this point, it appears a defect may be the culprit of why the results are less than stellar. 
Patrick has asked me to post the report and he'll comment on what the data shows when he gets a chance.
I'm hoping to work out something with the guys at JL to get a better test subject.

The new data is posted in the OP and is titled "12w6v2 2 ohm Retest". 
Here's a link:
http://www.diymobileaudio.com/forum...660250-jl-audio-12w6v2-12w6v2-2ohm-retest-pdf



Also, Patrick is going to host the Klippel reader file so that I can post the _raw data file_ which allow you all to view the data I get. You download the reader, I save the data file, post up a download link and you get to view it directly, in all its glory. I'll still publish the report to the site for you to download, but the addition of me posting the klippel data file will give you all the ability to view all the various tests that go in to the LSI testing that I don't include in the report and view the timeline in detail. :thumbsup:
Patrick has also offered to write up a Klippel "what to look for and how to interpret the results" type thread which will give us even more insight and he has signed on to be a reviewer of all my data and will do his best to discuss the data as it is posted in the future so we understand what it _really _means.

I'll also be retesting all the drivers whose data I've posted, now that I have some more insight in to the test. Those should be complete by the weekend. Look out for a generic Klippel thread which will discuss these topics in further detail. I don't want to clog up this thread with all of that. 

Patrick, THANK YOU.

Enjoy!

- Erin


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## specc00 (Jan 6, 2011)

thanks for all the info


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## cvjoint (Mar 10, 2006)

Interesting, an inductance limited xmax in a subwoofer. 

I presume Bl could have dropped over time since this is an old sub. Maybe the new ones will do better. Looking forward to the retests.


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## Redrock (Jun 6, 2011)

Thanks Erin for all the hard work!
I think the data on the JL sample is pretty clear so its probably time to move on to other speakers. I want to go over the data and help make sense of what we are seeing and how I came to the conclusion that this speaker is probably defective.
First a little overview of how the Klippel Distortion Analyzer (DA from now on) is set up and gets its data for Large Signal Identification (LSI).
1. LSI does not perform direct measurements. It imports Re, BL, Mms values from a small signal measurement and uses them as the starting point for a non-linear electro-mechanical model. Voltage and current are measured during the test and from this the model values are modified to fit the measurements. 
2. The curve fit model is only accurate if the speaker is excited enough to reach the non-linear portions of the response. To make this happen we have to push the speaker as close to its normal operation limits as possible. These limits are defined by the LSI "Protection" values. These are:


Upper temperature limit to prevent coil damage
BL and Compliance percentage change
Maximum power limit.

The test power is limited by whichever of the 4 limit values is hit first.

3. Ideally the test is limited by a BL or Compliance percentage change that is great enough to see the non-linear values of both. If we want to see where the BL has dropped to 70% and compliance to 50%, we need to reach limits that are beyond these values. If this happens, then we will see non-linear limit values (XBl, XC, XL, Xd) that are fully resolved. A good analogy is that you can't really know how fast a car will go until you take it up to its top speed. 

Enough of the operation for now. Lets look at the JL data.

On this sample neither the BL or C limits were hit. The speaker mechanically bottomed (neck joint to front plate) first. The limit was set by a maximum power level to prevent bottoming during the test.
This was enough to see a 70% XBL value of 12.9, but not enough however to see the XC Value (test shows >20.4) In fact the C protection value at the end of the test shows that at peak excursion of +/- 20mm, the compliance only varied to 84% of its starting value. This explains the unresolved shape of the Kms(x) curve. (The curve fit for the compliance didn't have enough range to define the shape_

The BL(X) curve did resolve, however it has a very asymmetrical shape. Looking at the BL Symmetry Range graph you can see this even more clearly. The red dashed line shows were the coil center position should be for symmetry. The correct position is about 6mm forward of where it in on this sample. The line stays at 6mm throughout the full excursion of the speaker showing that this is a static offset. This means that either the coil was assembled 6mm back from a center position, or that somehow the speaker has become dished so that the rest position is pushed back in the basket. 6mm of coil offset is way off any production spec that JL would allow and if the offset was part of the design, it would be in the out direction. I have seen many speaker samples come to me with this issue and invariably the cones have been pushed in by setting the speaker on it face or by packing materials pushing the cone in during shipping. My guess is that is what happened here.

Over the next few weeks Erin will get more data up and I will help "diagnose" the results as well as build a better overview of what Klippel data means in the real world. 
I have been really lucky to been given a DA system (with every module) about 9 years ago to do testing for Voice Coil Magazine. During that time I have tested thousands of speakers. It has been an amazing education into speaker design. 
I am happy to pass some of this on to people who love speakers like I do. I was there in the very beginning when DIY was about the only way to get quality sound in your car. I put on what was probably the first Crank-it-up contest at Texas Stadium in the early 80's (This was Wayne Harris's first contest and he won). I am really happy to see DIY still going strong.

I have put a copy of the Klippel Reader software on my FTP for anyone who wants to look at the raw data files. This is really interesting stuff and I will be going over each graph type and its meaning over the weeks to come.
ftp://ftp.redrockacoustics.com
User: Klippel (upper case K)
PW: klippel (lower case k)

Patrick

(Just got a note from JL that they are going to provide a new sample for testing - the thread lives on)


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## ErinH (Feb 14, 2007)

Thanks Patrick!

Guys, I'll provide the klippel data via Patrick's FTP site sometime this weekend.

Edit: Patrick, I'm having trouble accessing the FTP with the info you gave.


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## Redrock (Jun 6, 2011)

Got the FTP up. Thanks for the heads up!


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## msmith (Nov 27, 2007)

To address cajunner's concerns:

If you saw how W6v2's are built, you would see there is really no opportunity to mess around with coil alignment or anything else... All the parts fit together in a very precise, predictable manner. There is also no effort to "protect" the woofer with deliberate coil shifting in the design spec (this wouldn’t work, anyway). There is a very slight deliberate outward coil shift of 1 mm, when new, to account for suspension sagging over time, but not the kind of gross shift that is being seen in Erin's tests. The design goal is linearity.

One of our engineers, Brett Hanes, has been in touch with Erin and will be sending a new 12W6v2 to him... We pulled three units from stock and tested them all (and they all tested almost identically and within spec) and we are sending one of those. This way we can compare Erin's measurements to our own Klippel measurements.

If you don't want to trust us, Erin can call around and find a 12W6v2 local to him, in a dealer's stock, and I will be happy to facilitate making it available to Erin free of charge. Have the dealer contact me and I'll replace the woofer for the dealer on our end. Erin, just make sure it's a new woofer and talk to Brett about break-in and all that stuff prior to testing it.

Nobody is trying to pull the wool over anyone's eyes here. We know how our woofers perform and how they measure, and we know that the one Erin has is out of whack. We would be happy to put it on our own Klippel to confirm the accuracy of Erin's rig, too.

Best regards,

Manville Smith
JL Audio, Inc.


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## BlueAc (May 19, 2007)

That is an awesome gesture... A company going above and beyond. Gotta love it.


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## ErinH (Feb 14, 2007)

^ Manville, I've got one local dealer and just gave them a ring. No w6's in stock.


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## [email protected] (Jun 12, 2008)

msmith said:


> To address cajunner's concerns:
> 
> If you saw how W6v2's are built, you would see there is really no opportunity to mess around with coil alignment or anything else... All the parts fit together in a very precise, predictable manner. There is also no effort to "protect" the woofer with deliberate coil shifting in the design spec (this wouldn’t work, anyway). There is a very slight deliberate outward coil shift of 1 mm, when new, to account for suspension sagging over time, but not the kind of gross shift that is being seen in Erin's tests. The design goal is linearity.
> 
> ...



This is where JL shines, you cant beat that.


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## msmith (Nov 27, 2007)

bikinpunk said:


> ^ Manville, I've got one local dealer and just gave them a ring. No w6's in stock.


Erin... use our dealer finder... there are three dealers in the Huntsville area. I'm sure one of them has one in stock. I would tell you to just order one from our dealer-fulfilled web store on our website, but I wouldn't want anyone to think that our secret agents intercepted the order and slipped in a ringer.


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## trojan fan (Nov 4, 2007)

msmith said:


> To address cajunner's concerns:
> 
> If you saw how W6v2's are built, you would see there is really no opportunity to mess around with coil alignment or anything else... All the parts fit together in a very precise, predictable manner. There is also no effort to "protect" the woofer with deliberate coil shifting in the design spec (this wouldn’t work, anyway). There is a very slight deliberate outward coil shift of 1 mm, when new, to account for suspension sagging over time, but not the kind of gross shift that is being seen in Erin's tests. The design goal is linearity.
> 
> ...



A real stand-up company.... thanks Manville, you and your company should be applauded


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## cvjoint (Mar 10, 2006)

Redrock said:


> Thanks Erin for all the hard work!
> I think the data on the JL sample is pretty clear so its probably time to move on to other speakers. I want to go over the data and help make sense of what we are seeing and how I came to the conclusion that this speaker is probably defective.
> First a little overview of how the Klippel Distortion Analyzer (DA from now on) is set up and gets its data for Large Signal Identification (LSI).
> 1. LSI does not perform direct measurements. It imports Re, BL, Mms values from a small signal measurement and uses them as the starting point for a non-linear electro-mechanical model. Voltage and current are measured during the test and from this the model values are modified to fit the measurements.
> ...


That was one of the best reads ever! Please come again. 



msmith said:


> To address cajunner's concerns:
> 
> If you saw how W6v2's are built, you would see there is really no opportunity to mess around with coil alignment or anything else... All the parts fit together in a very precise, predictable manner. There is also no effort to "protect" the woofer with deliberate coil shifting in the design spec (this wouldn’t work, anyway). There is a very slight deliberate outward coil shift of 1 mm, when new, to account for suspension sagging over time, but not the kind of gross shift that is being seen in Erin's tests. The design goal is linearity.
> 
> ...


You guys have a Klippel machine? You mean you don't build speakers by sitting on the couch and listening? 

I remember you guys posting Klippel tests of the 8" when you got it out. Great product support and engineering then, great now. :thumbsup:


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## ErinH (Feb 14, 2007)

Went to a local shop in Madison, Al called "Sound Depot" and picked up a 12w6v2 off their floor, among the 6 or 7 they had sitting there. Helpful dudes. 

Here's some unpacking pictures and a pic of the receipt just to quash any conspiracy theories.


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## tintbox (Oct 25, 2008)

Nice.


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## ErinH (Feb 14, 2007)

the new w6 is getting some 20hz love right now and for the next 2 hours with ~0.60" 1-way excursion. I took a video of this and will upload later (note: in the video I say excursion at 0.80" but after I should have said 0.60").

I did a pre-break-in test and will do another test after break-in to see how/if the two differ.

The pre test shows Bl & Kms symmetry to be much better, though the Kms results trend the same as before. 
I'll post both sets of data (pre/post break-in) tonight or tomorrow.


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## ErinH (Feb 14, 2007)

some break in testing media...


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## b&camp (Jan 27, 2011)

this video is private. :/


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## ErinH (Feb 14, 2007)

should be good now.


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## highly (Jan 30, 2007)

bikinpunk said:


> Besides, Todd's the caffeinated one.


^ QFT...

I'd like to take a moment to extend my sincere thanks to both Patrick for coming to the forum to bring us the wisdom of his experience and to Manville for going FAR above and beyond in providing Erin not only with his pick of 12W6's but the direct support of your Lead Engineer. It is due to the actions of people like yourselves that DIYMA has become what it is!

Thanks, gentlemen, and thank you Erin for all of your hard work. 

-Todd


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## pionkej (Feb 29, 2008)

This thread is so full of OS DIYMA type win it's unbelievable. Good discussion, help and contribution from all over the place. Thanks to Erin, Manville, and Patrick at RR for moving this thread forward. I'm excited to see the new results.

Erin, that stand turned out awesome BTW. It was great watching the video and seeing the sub going crazy while the stand held frim. Good job to you sir.


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## DS-21 (Apr 16, 2005)

Hmm. Dished suspension likely due to packaging or use that squished the suspension.

I wonder if the lesson here is really "always fire drivers vertically, if you want them to last and to get maximum linearity out of them." 

And, secondarily always store them vertically, too.

I thought of that also when I saw a pair of KEF KAR 690Q's on eBay recently with clearly sagging suspensions.


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## cvjoint (Mar 10, 2006)

DS-21 said:


> Hmm. Dished suspension likely due to packaging or use that squished the suspension.
> 
> I wonder if the lesson here is really "always fire drivers vertically, if you want them to last and to get maximum linearity out of them."
> 
> ...


Dito. I'm also thinking "old school" is to be avoided as well. Speakers age, period. Heck, every component ages. Back when I had 7 Polk amps I could tell which ones where older by how much voltage they put out. I kept on changing them from woofer duty to tweeter duty.


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## Redrock (Jun 6, 2011)

Sagging Suspensions, Aging and Abuse.
In my experience a new driver sitting on the shelf in good packaging - vertical or horizontal won't sag. 
Sagging on a initially perfect driver can be caused by a number of things. Physical offset by poor packing is very common on the drivers sampled to me. Putting packing material in front of the cone seems like an obvious issue, but many times companies will hand a raw driver to their shipping guys who just don't understand. Original packing can also be an issue. I just went through 4 samples of a pro sound driver from a very well known high end manufacturer. They shipped the first 3 in the beauty (inner) box with the basket edges protected by about 3/8" of cardboard. the cast baskets cracked on all three.
Sagging can also happen over long periods of use or high levels of excursion. This is caused by spiders that are poorly designed or matched to the edge geometry. In the ideal speaker design, the spider and edge become non-linear at about the same time, however the edge hits its mechanical limits first. If the spider is required to mechanically stop the speaker from over-excursion (hard bottoming) then it will invariably break down. The glue holding the fibers together releases and the stiffness of the spider is gradually lost. If this happens asymmetrically then the spider becomes biased and will cup in either direction.
The other very common cause of a cupped spider / displaced suspension is a poor fit between cone body, basket and spider. It is very common to see speakers that were designed with 0 spacing between the cone neck and the neck of the spider. If any tolerance is off or if there is a glue bead required between these parts, you will see a bias between the natural rest position of the cone and spider. Many times the initial stiffness of the spider before break-in masks this. However when the speaker is broken in or worse still, over-driven, the spider looses its stiffness and the stiffness of the edge pushes the cone assembly down into the basket. 
Klippel shows this clearly with a uniformly biased BL(x) and a similarly biased suspension(Kms(x)).
Maybe 10% of the low cost speakers that I see have this issue. It makes me wonder how these speakers were tested and made it to production. The bias is often very easy to see.
My experience with JL speakers is that they are engineered with all of the clearances properly aligned - in fact they own patents on methods to make sure this is the case. They are also pretty much bullet proof. A few years ago I was asked to do an accelerated life test on the 6 top 12" woofers in the W6 price range for one of their competitors. This was a brutal ramped excursion/thermal test that ultimately brought each woofer to failure. After each power step sequence, the speakers were run through an LSI test. When all of the data was tabulated, the JL was the second last to break (against a woofer with a larger coil diameter). However it held its parameter set far better than the other speakers and failed by burning the coil. All of the other speakers in the test failed mechanically. If you are a speaker engineer, this means the JL actually won the test. It stayed linear, and didn't break until the coil failed.

Enough rant for today.
Patrick


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## ErinH (Feb 14, 2007)

16 viewers right now... wow...

Brett's 12w6 should be here today. Hopefully I'll get a chance to test it tonight. I have some suspicious regarding some of the test results previously so will spend some time triple checking this factor to see if it's causing bias in the results.

Stay tuned...

- Erin


PS: Patrick, you've got email.


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## Redrock (Jun 6, 2011)

No Mail yet Erin. Please send again.


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## ErinH (Feb 14, 2007)

Testing the storebought woofer...
I beat on this thing. Found that 220w was about the limit when I dropped protection of Bl down to 25%.
Cmin would get just below 70% a couple times and when it did, the offset line I had for spring factors showed a "u" trend as seen in Patrick's testing. In these cases, however, C never got to 65% without popping loudly (I suppose this is a hard bottom, or is it spider snap???... same thing???).
With that, I backed off and kept the test at a constant 220w which kept the woofer right on the edge of of getting whooped MMA style. 

Results are attached. Certainly not a symmetrical curve for C/K, but Bl looks better than the previous sample with only 3mm offset this time instead of 7mm like the other driver.
I'll ask Patrick if he can provide some narrative for the test results.



*I've attached a rapidshare link to the data here.* 
https://rapidshare.com/files/2057465061/12w6v2_Store_Model___2ohm_Final.kdb
At some point I'll try to figure out a way to post the results here directly so you guys don't have to wait for the rapidshare site to allow you to download the file.

Download the klippel reader software Patrick provided (linked below) to see the data in it's entirety.
I'll put it in to report format once I get a chance, but I thought this would be a great way to get people looking at the data files since Patrick has been nice enough to provide us with a file reader on his FTP.

Here's Patrick's FTP info:


Redrock said:


> I have put a copy of the Klippel Reader software on my FTP for anyone who wants to look at the raw data files. This is really interesting stuff and I will be going over each graph type and its meaning over the weeks to come.
> ftp://ftp.redrockacoustics.com
> User: Klippel (upper case K)
> PW: klippel (lower case k)
> ...





On another note, JL provided me with a woofer they tested directly. I'll be testing that sometime in the next few days and post up my results.


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## BuickGN (May 29, 2009)

bikinpunk said:


> Testing the storebought woofer...
> I beat on this thing. Found that 220w was about the limit when I dropped protection of Bl down to 25%.
> Cmin would get just below 70% a couple times and when it did, the offset line I had for spring factors showed a "u" trend as seen in Patrick's testing. In these cases, however, C never got to 65% without popping loudly (I suppose this is a hard bottom, or is it spider snap???... same thing???).
> With that, I backed off and kept the test at a constant 220w which kept the woofer right on the edge of of getting whooped MMA style.
> ...


I can't download the results from work but how much excursion did it take before it popped/bottomed?


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## ErinH (Feb 14, 2007)

it was getting to around 25mm, IIRC. _Well _beyond rated xmax (16.5mm IIRC). 

Look at the data; it lists excursion @ distortion limit (B of 70%, C of 50%, etc). In the data, you can open up the properties tab and change the threshold values to whatever percentage you want to get a feel for how the distortion limits affect the respective xmax value. Again, the distortion threshold parameters DO NOT govern the xmax of test. It's an 'after the fact' calculation that is based off the curve of the test, and then uses the threshold percentage to align this value. 

Xmax is limited by the protection parameters input in the "protection" tab. You'll notice that, IIRC, my protection parameters are Bl @ 25%, C @ 50%, Temp @ 180k (delta), and Power @ 220w. 
These values allowed Bl to reach ~ 25% while C never went below ~65%, and typically stayed around 71%. Like I said above, when C would dip below 70%, down to around 65%, the xmax would increase quite a bit and you could hear spider snap (I believe that's the correct term, Patrick can clarify). You can see this actually occur by viewing the Temperature/Power chart in the data. When I reach a high power value and the power takes a STEEP nosedive to a very low number, this is the point where the driver exhibited the 'pop' noise I speak of. This happened twice and was my sign to back off the power. 

The lower you set the protection %, the more aggressive the test is. This is one reason why better data is gathered by lowering the protection values because the test reaches outer bounds and is able to draw a curve fit more accurately. Think of it as drawing a graph on a piece of paper. If you have two points, you can only achieve a line. If you have 10 points, you have more flexibility in the shape you draw. Those points are dictated by the test and the more data you can get, the more accurate the test.
Though, I'd have to ask Patrick to explain exactly how these percentages work. I'm still a bit perplexed as to how a lower value allows for more severe testing, unless the percentage is 100%-Protect%, which then would mean I'm at 75% overshoot for a 25% Bl protection. (and 50% overshoot for a 50% C protection). Patrick, think you could take the reigns on this if I'm off base?


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## ErinH (Feb 14, 2007)

Something worth noting, as I'm not sure who knows this:
These tests are done with a bandpass of 10-400hz. This is automatically selected by the Klippel machine based on Fs. I let it do its thing. I can test at different bandpass if I want by overiding the automatic portion, however, I don't. 


I don't recall the specific equation the Klippel uses to get the bandpass, but I believe it's something like this:
HPF: 0.25*Fs
LPF: 8*Fs

So, for the JL, with an Fs of ~ 30hz, it would be played between 7.5hz - 240hz, though the Klippel rounded to make the auto range 10-400hz in my tests.


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## Wheres The Butta (Jun 6, 2009)

just wanted to say thanks. I really appreciate all the effort and the great coordination going on.


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## toolboy (Jun 6, 2011)

bikinpunk said:


> it was getting to around 25mm, IIRC. _Well _beyond rated xmax (16.5mm IIRC).
> 
> Look at the data; it lists excursion @ distortion limit (B of 70%, C of 50%, etc). In the data, you can open up the properties tab and change the threshold values to whatever percentage you want to get a feel for how the distortion limits affect the respective xmax value. Again, the distortion threshold parameters DO NOT govern the xmax of test. It's an 'after the fact' calculation that is based off the curve of the test, and then uses the threshold percentage to align this value.
> 
> ...


The Klippel limit percentages are a % of the "at rest" value. 

So if your baseline (peak) BL is 10, a 50% BL protection parameter will limit the test at BL = 5. If you set the BL limit at 25%, the test will run until you hit a BL value of 2.5. Same for the Cms limit. 

So, lower percentages mean a much greater change from the rest value. Because of this you have to swing MUCH more excursion (and use much more amp power) to get to these "lower percentage" limit values. 

- Brett
Sr Research Engineer
JL Audio, Inc.


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## Redrock (Jun 6, 2011)

Erin,
the protection limits are the delta from Small signal values. If you use 25% BL then you are telling it to limit when the large signal BL has reached 25% of initial value. For the JL the starting value is 10.82. So the voltage will limit when the BL reaches 2.7 (25%). The lower the delta value for BL and C the harder you push the driver.

Store Bought W6
This looks like a good driver. A tiny bit of BL offset but certainly within production tolerance, and not enough to cause any performance issues.
BL(x):
The BL(x) curve shows good symmetry with valid data well past the 70% point.
BL Sym:
This is a better way to look at the symmetry than the BL)x) curve. The red line is the center symmetry at all excursion points. The grey line is the window of accuracy for the red line. At very low excursions the BL is very linear and it is almost impossible to know the exact +/- range. As the coil moves further in and out of the gap, the relative change in BL increases and the curve fit can be more accurate. At 15mm of excursion the accuracy window is very tight and the asymmetry value is 1.1mm. At 25 mm, the window is even tighter and the assymetry is .76mm. I would say the correct value is somewhere between these say .9mm. This is really good for a high excursion woofer. The straight line also tells use that the driver is stable at high excursions. There is no offset at the excursion increases.

Kms(x)
You do begin to see that edges of the compliance on this curve and the delta compliance reached about 63%, but it is still not enough to define the corners of the response. There is really nothing that can be derived from this curve. This does not mean anything negative about the driver however. When it is put in a sealed box, the box compliance will control the maximum excursion. In the case a very linear suspension is a good thing.
The BL(x) range is enough to define the X BL at 70% as 15.5mm.
The Kms(x) curve is not enough to define the Xc however and it is shown as > 24.1mm

More on the Inductance curves and relative distortion values later...
Patrick


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## ErinH (Feb 14, 2007)

Droppin' knowledge!!!!! 

Thanks, guys.
I have ran the test at 50% values before. I was just under the impression that lowering those values would give you more telling data and draw the curves more accurately. While testing, I watch the values lower and push the driver a bit until I'm comforatable with its mechanical limits and then I stop the test and start over. 
I'm not 100% sure I'm following exactly what you guys are saying but I do understand it a bit more. Can either of you embelish a bit more (or can we discuss it on the phone) to make sure I understand this correctly?



Brett, glad to see you made it over. I appreciate your input.


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## ErinH (Feb 14, 2007)

Redrock said:


> Kms(x)
> You do begin to see that edges of the compliance on this curve and the delta compliance reached about 63%, but it is still not enough to define the corners of the response. There is really nothing that can be derived from this curve. This does not mean anything negative about the driver however. When it is put in a sealed box, the box compliance will control the maximum excursion. In the case a very linear suspension is a good thing.
> The BL(x) range is enough to define the X BL at 70% as 15.5mm.
> The Kms(x) curve is not enough to define the Xc however and it is shown as > 24.1mm
> ...


Important to note. Thanks.
For those wondering why I didn't push this harder... the simple reason is that the audible pops during the test were major cause for concern for me and what caused me to stop at the point discussed above. I might be able to push it further, but I'm honestly not okay with doing that on someone else's driver.


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## ErinH (Feb 14, 2007)

I had previously tested this driver at 50% protection values. I'll post that data up later.


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## quality_sound (Dec 25, 2005)

I haven't been posting much as of late but this is the kind of thread that has been SORELY missing for a great long while. Big thanks to Erin, Patrick, Brett, and Manville for, at least for this thread, sparing us from the litany of "which sub is best" type of threads and getting us back to our roots. 

Cheers fellas.


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## ErinH (Feb 14, 2007)

Thanks, Paul.

I think Patrick, Brett, Manville, and myself are all after one thing: accurate and truthful data.
I don't really care what it looks like as long as I believe it's valid. What I mean is simply: I have no bias or agenda. No desire to have one speaker test good while another tests bad. I want to know what a driver does but I also (with the help of Patrick) want to explain what is going on. That's why I'm making such a strong effort to talk with both Patrick and the guys @ JL regarding the test. 
I think Manville and Brett both understand my goals here. Luckily, they're on track and aren't pushing back like some manufacturer's might do. This is evidenced not only by their willingness to both send me additional samples but to also discuss testing and educate me a bit more about the testing.

I know I'm in good hands with the company I've kept regarding my role as the Klippel tester for this site. Patrick is a huge help and a great resource not only to myself but to this site as well.

Additionally, I've always held JL in high regard; always had great service in the 3 times I've had to contact CS for one reason or another. They never skip a beat and never accuse. Great company and this thread only furthers my sentiment. As a tester, there's nothing more stressful than having a mfg come to the board and try to put you on blast. They have done nothing of the sort and have done nothing but make me feel, dare I say, appreciated. 

- Erin


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## quality_sound (Dec 25, 2005)

Agreed. JL and it's employees have ALWAYS been amazing to deal with. Manville helped me source an amp from a stateside vendor last year and there are very, very few manufacturers that would have even bothered to reply. One of the worst days in my retail career was when the owner decided to drop the line. It was a total business decision based on the distance from the nearest JL dealer, but it was a sad, sad day.


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## BuickGN (May 29, 2009)

Talk about an all star cast in this thread. I've probably refreshed it 20 times today. As someone who has nothing useful to add I just wanted to say thanks to all involved for this kind of data and thanks to bikin for answering my question. The only reason I asked is when in IB form, I estimated my excursion from the 12W6 to be around 2" peak to peak before adding the subsonic. Just wanted to see if I was off or if it was possible.


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## cvjoint (Mar 10, 2006)

bikinpunk said:


> Testing the storebought woofer...
> I beat on this thing. Found that 220w was about the limit when I dropped protection of Bl down to 25%.
> Cmin would get just below 70% a couple times and when it did, the offset line I had for spring factors showed a "u" trend as seen in Patrick's testing. In these cases, however, C never got to 65% without popping loudly (I suppose this is a hard bottom, or is it spider snap???... same thing???).
> With that, I backed off and kept the test at a constant 220w which kept the woofer right on the edge of of getting whooped MMA style.
> ...



That is a serious amount of information on that link! Thanks Erin, Patrick for putting this together. I for one prefer this type of data file far far better than the pdf but I'm afraid most of our users would prefer the latter. 

BL and CMS look great on this one. There a lot more motor force and it's a lot more symmetrical. 1mm shy from the manufacturer's rating is not bad at all. If only all driver would test this close we could actually use the parameters that come in the box for modeling. How nice would that be? 

I'm sure I'm not the only one thinking this, but how about that inductance? This is a very robust driver in every other aspect but there is a lot of improvement left in the LE curve. If possible, I'd love to hear about the engineering decisions regarding this parameter. DIYers have been drooling over shorting rings for a long time. It would nice to know what the goals where in this respect and what the implications are for the curve that resulted from the testing. 

A+ to JL for trusting on a new driver to do better, and of course the results that backed that up. 

Patrick, looking forward to more lessons. I now find the symmetry graph to be a lot more useful. I had no idea that it could vary with displacement.


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## ErinH (Feb 14, 2007)

*Patrick's FTP has been updated with a few things.* 

#1 was the test of the store 'bought' woofer pre and post break in. Break in, as I mentioned a few posts back, was done like so:
20hz for 2 hours at ~xmax. 
I posted the corresponding T/S parameters as well. Now we can carry over the "break in" argument in this thread.


Secondly, I added the test results for the woofer JL sent me after they tested it on Friday. This test is called the "... 8 ohm" test. I tested this driver at 8ohm to mimic what they had done. I'll re-test at 2 ohm tomorrow to see how it compares to my previous driver tests at 2ohm.

Enjoy!!!

- Erin


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## ErinH (Feb 14, 2007)

well, I'm floating around right now. I got the SI sub and tested it against what Patrick had gotten for his results this weekend. 3 different tests that I couldn't complete... The problem I'm having now is my amp; it's not giving me enough juice even though it's rated for 2400x1 @ 4ohm (bridged). I may be on the hunt for a new amp but I don't have the $300+ for a good pro-sound sub needed for high powered tests. I'm hoping I can get a loaner amp just to make sure that my amp is the issue. Someone did the fan mod and I'm thinking it's just getting too hot and turning off during the test. 500w constant for 10 minutes will do that. 
if this stays the case, I may be relegated to small driver testing only. 

while my results were trending the way of Patrick's for the SI sub, there's no way for me to know for sure if I'd get the same thing. And, that's our 'calibration' sub for comparison. Until I can verify his results with my own, I'm in Klippel limbo.


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## 60ndown (Feb 8, 2007)

i like my 12w6v2 better then any sub ive ever used (even more then my w7)

w7 was great at getting real low and loud but it got weird sometimes, the w6 never gets weird on anything i throw at it.

trust yer ears and throw all these high tech toys to teh kerb


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## highly (Jan 30, 2007)

I'm willing to make you a nice tinfoil hat if you'll stop with the stupid nonsense.

Deal?


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## Redrock (Jun 6, 2011)

Erin,
sorry this has become frustrating. I still think the first goal is to make sure your system is working like mine. It is the most up to date and fully calibrated system - new from Klippel 6 months ago, the latest software rev, and it goes through monthly testing as the heart of my speaker lab. I have been able to compare its data against many other DA's around the world and they all seem to match very well. Once we verify your system on some smaller drivers, we need to explore the limits to make sure we know where they are.
Towards that end, I am going to pull a handful of samples from my storage, test them again and send them out to you. Probably a bunch of PX speakers. Some may be prototypes that showed clear non-linearities so they will be really good for use as references. I will pick a range of sizes. I should be able to get these out before the end of the week.

Cajunner and others who are concerned about hiding / holding back data, remember that we are not getting anything out of this other than the joy of passing along cool information. Erin has been working hard to make sure that his system is working the way it should and learning the fairly complicated function of the DA. He is already way ahead of most of the users that I tutor at this stage.
My company is an independent lab. I get money for testing evaluation and loudspeaker design. JL by the way has never been a client. The idea to pass on full database files and the reader was my way of offering up the full set of data as opposed to a few windows. There is far more there than the just symmetry curves (as cool as they may be).
The end goal of all of this is to be able to give good data and information about how to interpret it, on as many speakers as possible. Got to make sure the data is solid and repeatable first - that's just good science.

While you are waiting...
Let me know if anyone is interested in seeing some data on the Parts Express Dayton Neo 3". I just finished an R&D project of optimizing this driver and I could show the steps in the process of getting these speakers Dialed In. Maybe start another thread on general klippel testing and education?

Patrick


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## ErinH (Feb 14, 2007)

Patrick, thanks for that. I appreciate it. Sometimes people have no idea what is going on behind the scenese so they speculate, outside of any realm of knowledge and what we wind up with is an e-fight. I'm sorry everyone has to see that kind of stuff but there's only so much I can take as a person who has poured many hours of his life in to this project and then get it shoved right back in my face. I've said my piece and am moving on. 


On to your proposal; certainly I'm sure I speak for most of us that we'd love that opportunity. Feel free to make your own thread (if there are limitations as a new user that doesn't allow this, let me know and I'll start it with whatever title you'd like so we can get the ball rolling).

In addition, I'd like to thank you again for all your help and words of encouragement.


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## sundownz (Apr 13, 2007)

bikinpunk said:


> well, I'm floating around right now. I got the SI sub and tested it against what Patrick had gotten for his results this weekend. 3 different tests that I couldn't complete... The problem I'm having now is my amp; it's not giving me enough juice even though it's rated for 2400x1 @ 4ohm (bridged). I may be on the hunt for a new amp but I don't have the $300+ for a good pro-sound sub needed for high powered tests. I'm hoping I can get a loaner amp just to make sure that my amp is the issue. Someone did the fan mod and I'm thinking it's just getting too hot and turning off during the test. 500w constant for 10 minutes will do that.
> if this stays the case, I may be relegated to small driver testing only.
> 
> while my results were trending the way of Patrick's for the SI sub, there's no way for me to know for sure if I'd get the same thing. And, that's our 'calibration' sub for comparison. Until I can verify his results with my own, I'm in Klippel limbo.



Cool -- so the SA-12 made it ? You can hang onto it for a while if you need to


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## ErinH (Feb 14, 2007)

Yea, sorry. I meant to contact you to let you know. Just been caught up with other stuff.

For those dissatisfied with the wait times, here's something I put up over the weekend. So, even when I'm taking downtime from the klippel, I'm still providing data to the forum...
http://www.diymobileaudio.com/forum...rs-pioneer-deh-p9-pioneer-800prs-testing.html


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## Redrock (Jun 6, 2011)

FYI,
I started a new thread on the Dayton ND90-4.


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## ErinH (Feb 14, 2007)

Results from the JL provided woofer (from their factory floor) last week:



you can see Bl looks better, but my suspension curves are still odd compared to what JL sent me for their results. I'm hoping Patrick's drivers can help me figure out what's going on here and see if the results are legitimate or not.


edit: well screw a goat... .my pdf file license expired. 
sit tight while I try to get this taken care of.


edit 2: pdf conversion software is expensive!!!!!! I'm posting the .png files (graphs) for now. this really sucks!


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## alachua (Jun 30, 2008)

its a bit of a hack, but you can insert the images into Word then publish as a .pdf. The file size isn't optimal and it is a bit slower than some of the other software, but if you have Word, it is free.


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## cvjoint (Mar 10, 2006)

bikinpunk said:


> Results from the JL provided woofer (from their factory floor) last week:
> 
> 
> 
> ...


Ahh shucks man! You should charge the forum members who want this format badly enough to offset the fee.


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## ErinH (Feb 14, 2007)

ironically, those who complain the loudest are often those who won't lend a hand at all. but, if they want to, feel free to shoot me a PM.


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## quality_sound (Dec 25, 2005)

^^^That would be cool. I think it's been done before though. Granted, it was in the 90s.


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## Brian Steele (Jun 1, 2007)

cajunner said:


> right, I'm not talking about making an enclosure, I'm saying bolt a pair of woofers face to face and have the klippel stand hold it like it was just the one woofer
> 
> I would like to know if the second-order distortion really does come down when both motors are acting on non-linearity, and if having an asymmetrical BL (ugly) actually can be corrected by the clamshell config.



Sounds like a pretty good idea to me....


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## SSSnake (Mar 8, 2007)

> hey, do you think you could test a pair of subs in isobaric mode?


Actually that would be awesome. I've always been told iso had these properties but I have never seen this demonstrated.


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## ErinH (Feb 14, 2007)

It would be interesting, but I'd have to build the rig solely for that purpose and I just do not have the time. Testing is about to slow to a creep for the next month while I focus on doing what I need to do at the house to get it ready to put on the market. *proving, yet again, I do have a life outside of klippel testing*


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## quality_sound (Dec 25, 2005)

cajunner said:


> right, I'm not talking about making an enclosure, I'm saying bolt a pair of woofers face to face and have the klippel stand hold it like it was just the one woofer
> 
> I would like to know if the second-order distortion really does come down when both motors are acting on non-linearity, and if having an asymmetrical BL (ugly) actually can be corrected by the clamshell config.



That's what I'm saying. It WAS done. It was an issue of CSR or CA&E. I think it was with Oz Audio subs.


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## quality_sound (Dec 25, 2005)

Was the Klippel even around back then? I don't know the equipment used but I remember the article. 

You can search just as easily as I can.


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## IceWaLL (May 30, 2005)

bikinpunk said:


> I do have a life outside of klippel testing*


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## Ricci (Sep 30, 2008)

This is a great and informative thread. Thanks to all involved, especially Patrick (I've been absorbing your Klippel tests in Voice Coil for awhile.). 

Teamwork is awesome.


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## Octopus Jonny (Oct 30, 2007)

Just wanted to say thanks to all in this thread sharing knowledge. Such interesting information.


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