Acoustic Elegance AV12-X D2!

[jmanpc 5,000+ posts]

Oh, and...

Then I guess you aren't very good at abuse //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

 

[its_bacon12 10+ year member]

people arguing have no experence what so ever that is laughable.. john plotted many enclosures, and said 1500 wouldn't danage the woofer, yet in 2.8 tuned to 31 i got uncontrolled excursion... yall are blabbing about damping box size etc but no nothing of the sort, then we have MR mines in 2.75 and sounds excellent.. u don't know what excellent sounds like..

i must have said it 1000 times the woofer had very little control over 50 i HAD to cross it that low to get decent output otherwise it would botton easily, i got pissed crossed it @ 70 played 1 song maybe 2min rooling the volume and what do you know??

Try to make your next response coherent.

 

[Koon 10+ year member]

Mine was a 15X, but you know my opinion.....

i meant to say are there any good/positive reviews on the 15" AV?

 

[John_E_Janowitz 10+ year member]

people arguing have no experence what so ever that is laughable.. john plotted many enclosures, and said 1500 wouldn't danage the woofer, yet in 2.8 tuned to 31 i got uncontrolled excursion... yall are blabbing about damping box size etc but no nothing of the sort, then we have MR mines in 2.75 and sounds excellent.. u don't know what excellent sounds like..

i must have said it 1000 times the woofer had very little control over 50 i HAD to cross it that low to get decent output otherwise it would botton easily, i got pissed crossed it @ 70 played 1 song maybe 2min rooling the volume and what do you know??

And I have said it as many times that above 50Hz has literally nothing to do with the suspension of the driver. The system compliance is dominated by the ENCLOSURE. Hoffman's Iron Law. You can't get around it. Below tuning in a vented box, there is virtually no compliance from the enclosure which is why it unloads. It takes very little power to drive the woofer to high excursions. That is what a highpass filter is for, also mistakenly called a subsonic or infrasonic filter. The point is to prevent the driver from over excursion. You argued with me over and over that a woofer should not need a highpass filter to protect from over excursion so I tried to explain it to you with models. I'll copy the basics here.

First, here is a graph of the AV12H in 2.5cf tuned to 33hz. The orange curve is with full range input to the driver. You can see with 1000W it is possible to exceed Xmax about 22-23hz. (with 1600W it will be much higher.) The idea is to take down excursion below tuning without affecting the output greatly above tuning. The 12db highpass (subsonic or infrasonic) with a Q of .7 will do this quite nicely. With the addition of the 30hz 12dB highpass you get the yellow curve.

This now keeps excursion well within limits. It now takes much more power to surpass the 23mm Xmax below tuning. Now, that assumes a 2nd order highpass with a Q of .7. Some amps have a higher Q filter above 1.0 that actually gives a bump and increases excursion over a limited range before lowering it. In that case it is a good idea to move it slightly higher to the same as your tuning frequency.

The other suggestion given was for a stiffer spider. This is not nearly as effective because the system is dominated by the enclosure and not the driver suspension. You need extreme changes in suspension stiffness to protect the driver below tuning. The following graph shows the original driver in green, suspension stiffness doubled in red and then 10x the suspension stiffness in the light gray.

You can see that doubling the suspension stiffness has very little effect until under 20hz. This is not in the area we are concerned with where we will run into the excursion limits of the driver. The light gray with 10x the suspension stiffness has more effect, but at the same time actually increases excursion from 28-30hz due to the raised Q of the driver. Excursion below that point is still coming very close to the 23mm Xmax. And now the Fs of the driver is moved all the way up to well over 50Hz.

Finally here is an image just showing the woofer alone in green, with 2x suspension stiffness in red, and with the 30hz 12dB highpass in yellow.

This shows clearly that a highpass is much more effective at preventing over excursion from the driver than increasing suspension stiffness.

That all assumes that the driver doesn't have a bent up cone, torn spider, and surround ripped off. I just don't have the ability to see how a woofer will model under those circumstances.

John

 

[nastyaudioman 10+ year member]

And I have said it as many times that above 50Hz has literally nothing to do with the suspension of the driver. The system compliance is dominated by the ENCLOSURE. Hoffman's Iron Law. You can't get around it. Below tuning in a vented box, there is virtually no compliance from the enclosure which is why it unloads. It takes very little power to drive the woofer to high excursions. That is what a highpass filter is for, also mistakenly called a subsonic or infrasonic filter. The point is to prevent the driver from over excursion. You argued with me over and over that a woofer should not need a highpass filter to protect from over excursion so I tried to explain it to you with models. I'll copy the basics here.
First, here is a graph of the AV12H in 2.5cf tuned to 33hz. The orange curve is with full range input to the driver. You can see with 1000W it is possible to exceed Xmax about 22-23hz. (with 1600W it will be much higher.) The idea is to take down excursion below tuning without affecting the output greatly above tuning. The 12db highpass (subsonic or infrasonic) with a Q of .7 will do this quite nicely. With the addition of the 30hz 12dB highpass you get the yellow curve.

This now keeps excursion well within limits. It now takes much more power to surpass the 23mm Xmax below tuning. Now, that assumes a 2nd order highpass with a Q of .7. Some amps have a higher Q filter above 1.0 that actually gives a bump and increases excursion over a limited range before lowering it. In that case it is a good idea to move it slightly higher to the same as your tuning frequency.

The other suggestion given was for a stiffer spider. This is not nearly as effective because the system is dominated by the enclosure and not the driver suspension. You need extreme changes in suspension stiffness to protect the driver below tuning. The following graph shows the original driver in green, suspension stiffness doubled in red and then 10x the suspension stiffness in the light gray.

You can see that doubling the suspension stiffness has very little effect until under 20hz. This is not in the area we are concerned with where we will run into the excursion limits of the driver. The light gray with 10x the suspension stiffness has more effect, but at the same time actually increases excursion from 28-30hz due to the raised Q of the driver. Excursion below that point is still coming very close to the 23mm Xmax. And now the Fs of the driver is moved all the way up to well over 50Hz.

Finally here is an image just showing the woofer alone in green, with 2x suspension stiffness in red, and with the 30hz 12dB highpass in yellow.

http://www.aespeakers.com/pics/AV12H_2.5cf_33hz_HP_vs_stiff_suspension.png[/ig]

This shows clearly that a highpass is much more effective at preventing over excursion from the driver than increasing suspension stiffness.

That all assumes that the driver doesn't have a bent up cone, torn spider, and surround ripped off. I just don't have the ability to see how a woofer will model under those circumstances.

John

Will you stop with the graphs. As stated, they don't mean anything. We will wait for the new runs to get out there and see what happens.

 

[John_E_Janowitz 10+ year member]

Will you stop with the graphs. As stated, they don't mean anything. We will wait for the new runs to get out there and see what happens.

I find it funny that now not only are my woofers being criticized, now the Theil Small parameters and electrical modeling that has been around since 1954 is being criticized as well. You can believe that they are not accurate if you wish and just give over everything to chance. I wish you luck witht he results. However, years and years of physics and electrical circuit modeling has proven the validity of these models. There is however a saying in engineering that "garbage in = garbage out". If you don't have accurate parameters to model what is going on, then you won't get valid results.

The primary parameters for a driver are the following. They are physical values that can be easily measured and verified both at small signal levels and at higher excursions.

* Sd - Projected area of the driver diaphragm, in square metres.

* Mms - Mass of the diaphragm, including acoustic load, in kilograms.

* Cms - Compliance of the driver's suspension, in metres per newton (the reciprocal of its 'stiffness').

* Rms - The mechanical resistance of a driver's suspension (ie, 'lossiness') in N·s/m

* Le - Voice coil inductance measured in millihenries (mH) (Frequency dependent, usually measured at 1 kHz).

* Re - DC resistance of the voice coil, measured in ohms.

* Bl - The product of magnet field strength in the voice coil gap and the length of wire in the magnetic field, in tesla-metres (T·m).

If you have accurately measured parameters and you know how the BL and Cms curves affect things at higher excursions you can model things very accurately both at low and high power. Now, that doesn't mean that you can just take what the modeling program shows for SPL in a box alone, stick it in a car and add the cabin gain to it and get that exact result. There are other variables introduced by the car. Just because you have 30dB of gain at low levels doesn't mean the transfer function is identical as the cabin begins to pressurize, panels begin to flex, etc. Any accurate model has to account for variables.

Then the best way is always to verify what you are modeling by measuring the results. The Scientific Method:

1. Define the question

2. Gather information and resources (observe)

3. Form hypothesis

4. Perform experiment and collect data

5. Analyze data

6. Interpret data and draw conclusions that serve as a starting point for new hypothesis

7. Publish results

8. Retest (frequently done by other scientists)

John

 

[nastyaudioman 10+ year member]

I find it funny that now not only are my woofers being criticized, now the Theil Small parameters and electrical modeling that has been around since 1954 is being criticized as well. You can believe that they are not accurate if you wish and just give over everything to chance. I wish you luck witht he results. However, years and years of physics and electrical circuit modeling has proven the validity of these models. There is however a saying in engineering that "garbage in = garbage out". If you don't have accurate parameters to model what is going on, then you won't get valid results.
The primary parameters for a driver are the following. They are physical values that can be easily measured and verified both at small signal levels and at higher excursions.

* Sd - Projected area of the driver diaphragm, in square metres.

* Mms - Mass of the diaphragm, including acoustic load, in kilograms.

* Cms - Compliance of the driver's suspension, in metres per newton (the reciprocal of its 'stiffness').

* Rms - The mechanical resistance of a driver's suspension (ie, 'lossiness') in N·s/m

* Le - Voice coil inductance measured in millihenries (mH) (Frequency dependent, usually measured at 1 kHz).

* Re - DC resistance of the voice coil, measured in ohms.

* Bl - The product of magnet field strength in the voice coil gap and the length of wire in the magnetic field, in tesla-metres (T·m).

If you have accurately measured parameters and you know how the BL and Cms curves affect things at higher excursions you can model things very accurately both at low and high power. Now, that doesn't mean that you can just take what the modeling program shows for SPL in a box alone, stick it in a car and add the cabin gain to it and get that exact result. There are other variables introduced by the car. Just because you have 30dB of gain at low levels doesn't mean the transfer function is identical as the cabin begins to pressurize, panels begin to flex, etc. Any accurate model has to account for variables.

Then the best way is always to verify what you are modeling by measuring the results. The Scientific Method:

1. Define the question

2. Gather information and resources (observe)

3. Form hypothesis

4. Perform experiment and collect data

5. Analyze data

6. Interpret data and draw conclusions that serve as a starting point for new hypothesis

7. Publish results

8. Retest (frequently done by other scientists)

John

Here is my thing. Many and I mean MANY folks stuck up for you on caraudioforum. These guys bought into your "knowledge" and graphs. Yes, on paper many things can look good. I can draw you a time machine if you want //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Problem I see is that the guys who bought from you on that forum which may only be 3 or 4, but those guys ALL had issues. I do give you repect on your service by refunding the money with no issue. MANY companies won't do that period. I also understand that suppliers can also be a hassel. But the real world hands on testing is what counts and in my eyes your subwoofers aren't performing in the car audio world well with reliability. I will highly recommend you go to the woven leads because silicone on the back of a subwoofer cone does not look good.

Now, you state that on a single 4 ohm woofer that when leads are woven it could cause coil rock. If that is such a huge issue with you and the woofers, are you measuring the silicone being put on the cone to make sure in fact that each globs weigh the same? IMO it looks like crap and cheap not too mention changes the mms and so forth when adding that. So are your parameters before or after the silicone?

As for my other questions that were un-answered, please let me know the many drivers with woven leads that failed with those issues you stated. Also, who uses 100% cotton spiders as well? Are you really using nomex or are your spiders cotton?

I am not bashing you or your product, but you will need to prove these accusations. I will be waiting for your response.

EDIT: Thought this was needed. YOUR response only, not someone trying to stick up for you //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[T3mpest 10+ year member]

I find it funny that now not only are my woofers being criticized, now the Theil Small parameters and electrical modeling that has been around since 1954 is being criticized as well. You can believe that they are not accurate if you wish and just give over everything to chance. I wish you luck witht he results. However, years and years of physics and electrical circuit modeling has proven the validity of these models. There is however a saying in engineering that "garbage in = garbage out". If you don't have accurate parameters to model what is going on, then you won't get valid results.
The primary parameters for a driver are the following. They are physical values that can be easily measured and verified both at small signal levels and at higher excursions.

* Sd - Projected area of the driver diaphragm, in square metres.

* Mms - Mass of the diaphragm, including acoustic load, in kilograms.

* Cms - Compliance of the driver's suspension, in metres per newton (the reciprocal of its 'stiffness').

* Rms - The mechanical resistance of a driver's suspension (ie, 'lossiness') in N·s/m

* Le - Voice coil inductance measured in millihenries (mH) (Frequency dependent, usually measured at 1 kHz).

* Re - DC resistance of the voice coil, measured in ohms.

* Bl - The product of magnet field strength in the voice coil gap and the length of wire in the magnetic field, in tesla-metres (T·m).

If you have accurately measured parameters and you know how the BL and Cms curves affect things at higher excursions you can model things very accurately both at low and high power. Now, that doesn't mean that you can just take what the modeling program shows for SPL in a box alone, stick it in a car and add the cabin gain to it and get that exact result. There are other variables introduced by the car. Just because you have 30dB of gain at low levels doesn't mean the transfer function is identical as the cabin begins to pressurize, panels begin to flex, etc. Any accurate model has to account for variables.

Then the best way is always to verify what you are modeling by measuring the results. The Scientific Method:

1. Define the question

2. Gather information and resources (observe)

3. Form hypothesis

4. Perform experiment and collect data

5. Analyze data

6. Interpret data and draw conclusions that serve as a starting point for new hypothesis

7. Publish results

8. Retest (frequently done by other scientists)

John

Silly John this is CAF. Where teenage kids take subs throw as much power as they can on to them and just beat on them. If it's not idiot proof it won't do well with this crowd, which I think says something inherently. There is nothing wrong with your woofers for a car application as long as the person using them knows the limits of the driver. Anyone who thinks you can't model overexcursion at various frequencies really needs to step out of the groundpounding CA bubble and look at actual stereo systems.

 

[sundownz Pro Seller]

Now, you state that on a single 4 ohm woofer that when leads are woven it could cause coil rock. If that is such a huge issue with you and the woofers, are you measuring the silicone being put on the cone to make sure in fact that each globs weigh the same? IMO it looks like crap and cheap not too mention changes the mms and so forth when adding that. So are your parameters before or after the silicone?

John is correct about woven leads on one side of the spider. It can cause non linear movement, and possibly coil rock.

If you look at, for example, a TC Sounds single coil sub... they weave the leads on both sides of the spider to keep it linear. One side is obviously not hooked up - but the lead is still woven there.

 

[NDMstang65 10+ year member]

Nick said;"It's funny Fi subs sound like a wet fart..If I remember right we've got 3 world title SQ cars running the subs? ......So tell me there slick, How many IASCA/USACi/MECA world championship cars are running low inductance and/or xbl^2 equipped woofers? I'll be waiting for that one." [Emphasis mine]

Since Nick wanted to compare the SQ of the Fi to low Le/XBL^2 drivers based on championships, and was apparently attempting to indicate the Q was a better driver because it won all of 3 whole championships ( //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif )........I pointed out that continuing that logic and comparing the L7 to Fi on the same basis results in the L7 being the "better sounding driver" since it has more championships and was used frequently in very competitive and critical classes.

In other words......I was pointing out he was using a straw-man argument that he did not want to continue down without making his position look even worse.

He seems to indicate otherwise;

Which tells me he has some sort of vendetta that he was attempting to continue in this thread......with every attempt resulting in him being politely put in his place by John //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

Since he's such a "realist".......he should really learn when not to open his mouth or be prepared to place his foot in it //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif Because that's all he's accomplished with the petty arguments he's attempted to start with John in this thread. I don't know the guy personally other than surfing the same general forums for the past 5 or so years........but over the past few weeks my e-respect for him has dwindled to nothing. Not that it matters much, I suppose.

The point was there slick that it comes down to the vehicle, the person behind the controls, and the install not the woofer and the techno-jargon that wins championships. Yes Eldrige and Biggs both won many titles using nothing more than..L7's. None are a highly technical woofer...with tons of graphs and theory and this should sound the best because of x,y, and z...they seem to sound fine in the right hands. But of course having a one-track mind like yourself and Mr. Bose neither of you could not see that i'm using a real world comparison...which should be done instead of theory in a lab. (Unless you are riding around in a 500' long anechoic chamber, then all of this does indeed apply 100% and you WILL hear a difference no doubt because hey, the graphs show it) Not comparing a product is inherently better than another one. But a technology that sounds "Horrible" that has been pretty standard in the industry for the past ohh...30 years or so? Seems to sound great.

I've never had a problem with John, Still do not have a problem with John, and John did not answer my one question. Can you audibly hear it and tell a significant difference in the environment in which it is in?

When you are in the bottom of the 9th, bases loaded, full count..do you swing and strike out or smack it out of the park? Can you actually hear what is being found in a laboratory environment, in a car, in this scenario and context that it is in.

He never once put my foot in my mouth...I never once cut on his product. He cut on some of our subs a few weeks back in regards to how "Foolish" one would be to make an American product which did irk me a bit that one would support outsourcing jobs instead of rooting for the home team so I put it in the back of my mind...

I don't have a vendetta against anybody (except bose, he's cute and i like him a lot). I call it how it is. Theory is great, it is a wonderful tool. Until you have to use theory and flashy signs to get people to believe the theory and flashy signs as the bible. Then at that point you are no more then a vacuum cleaner salesman of the 1960's that take money and run when nothing goes according to the theory and flashy signs. (Not saying there was not abuse here, because there obviously was)

If you can't see that and you do not dare ask well that's great in a lab how does it work out in the environment in which it is in you are nothing more than a cat that sees the laser pointer and runs after it..blindly, right into the wall.

 

[NDMstang65 10+ year member]

No, Nick mentioned that the Q has won championships and that makes it the ultimate driver. squeek pointed out that the L7 has won more than twice as many championships as the Q so it must be the better sounding driver. It's the exact same logic.
What pisses me off is that Nick comes into threads about other manufacturer's products and berates them, says they are crappy et. al when the other manufacturers don't go into every Fi thread and point out how cheap and shitty their drivers are. Really low life business tactics IMO.

Oh no no no.

Hold the phone, right there cutie.

I'm merely pointing out and wanting him to explain how does this theory apply to a real world scenario (Because many on here do not understand it and how if/when does it apply)

I never ONCE cut on his products (Others in this thread have, I have not and I will not because that is against the rules and the name of the game). If you have all the theory and all the pretty graphs...can you hear it in the car? The other thing I commented on was him thinking about using aluminum as a material for a SPL oriented speaker (Which is where he got to be a smart ass and comment about airplanes using aluminum and I just so happen to work a great deal on airplanes and tend to know a wee bit more about those materials). I advised that he did not do that because it would fold no matter how thick it was. Again, giving advice...not cutting on his products, but saving him time from wasting money tooling a cone to find out hey..he was right, it did break on this SPL speaker let's not do that.

I would have left him alone had he not made a comment a few weeks back about our stuff...so I figured I'd see if he really does know the environment that the stuff goes in, instead of an anechoic chamber and/or an open field.

I didn't throw the first stone there sweet cheeks. I never do. I just wanted to know how all of this stuff applies to the car that it gets put in since we are within the 'caraudio' context. I still don't have an answer as to if you can hear it or not.

If you are going to talk the talk that you've got a time machine, you better walk the walk and show that it really works and jump in it, because somebody like me will see flaws in the theory behind it and say...can you really time travel?

 

[bose301s 5,000+ posts]

This message is hidden because NDMstang65 is on your ignore list.

Much better!

 

[NDMstang65 10+ year member]

This message is hidden because NDMstang65 is on your ignore list.

Much better!

YES!

FINALLY!

(He'll log out and read it..he can't stand it)

 

[bose301s 5,000+ posts]

Yay!! No more hearing Nick's ignorance!!

 

[kendogg 10+ year member]

YES!
FINALLY!

(He'll log out and read it..he can't stand it)

He's on my ignore list as well. Just have to click 'view post' to see what annoying people have to say if you actually want to see it //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[bose301s 5,000+ posts]

He's on my ignore list as well. Just have to click 'view post' to see what annoying people have to say if you actually want to see it //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Amazingly I haven't ignored you.

 

[kendogg 10+ year member]

Amazingly I haven't ignored you.

I certainly wish you would //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[NDMstang65 10+ year member]

He's on my ignore list as well. Just have to click 'view post' to see what annoying people have to say if you actually want to see it //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Thanks for the heads up //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I'm going on vacation to the real world..we'll see yall on the flip side.

 

[bumpin buick 5,000+ posts]

Interesting, because if I recall I posted pics and vids of the sub in action... In a real world scenario.

Nick you and I have talked several times before. I will let John have his words with you but all I am trying to say is that if the graphs don't mean crap to you, then you are implying that you would like to see real world testing. I dropped his sub into the same box I had my FI BTL in. It doesn't get much more real world testing than that, does it. With out using any RTA software I can tell you that by ear his sub had much better range and response then the SPL subs I had tested in my recent challenge, the closest of which compared was the Sundown Z15 but besides that for range, his sub just walked the competition.

Again Nick I am not attacking you nor your product. Simply saying that if the technical side of it is not enough to prove its a good sub, what about my real life testing? I guess I would like to know what it will take to get the sub proven to the CA industry. Seems like there are too many bandwagons around the forums now a days that simply wont allow a new company in. You tell me what you would like to see Nick and im sure John will let me go ahead and test it exactly how youd like. I have no affiliation with this company but the fact that John came to my house with some subs and said "let loose" on them I respect. Not many companies would send in subs for people to just power test like crazy. I know for a fact FI/AA would never send out a sub to a normal user for them to power test. Which I must say I find very ironic as you guys use very rigorous in-house testing procedures on your subs, none of which I would find to be realistic, I guess I find it just as relevant then as Johns T/S testing if not more. I mean how much was that linear laser testing machine that you guys use? You have gone into detail on other testing procedures before but I can not recall them at this time, but you and I both know that its kind of weird to call John out on his testing procedures when FI/AAs are just as(if not more) lab oriented.

 

[NDMstang65 10+ year member]

Interesting, because if I recall I posted pics and vids of the sub in action... In a real world scenario.
Nick you and I have talked several times before. I will let John have his words with you but all I am trying to say is that if the graphs don't mean crap to you, then you are implying that you would like to see real world testing. I dropped his sub into the same box I had my FI BTL in. It doesn't get much more real world testing than that, does it. With out using any RTA software I can tell you that by ear his sub had much better range and response then the SPL subs I had tested in my recent challenge, the closest of which compared was the Sundown Z15 but besides that for range, his sub just walked the competition.

Again Nick I am not attacking you nor your product. Simply saying that if the technical side of it is not enough to prove its a good sub, what about my real life testing? I guess I would like to know what it will take to get the sub proven to the CA industry. Seems like there are too many bandwagons around the forums now a days that simply wont allow a new company in. You tell me what you would like to see Nick and im sure John will let me go ahead and test it exactly how youd like. I have no affiliation with this company but the fact that John came to my house with some subs and said "let loose" on them I respect. Not many companies would send in subs for people to just power test like crazy. I know for a fact FI/AA would never send out a sub to a normal user for them to power test. Which I must say I find very ironic as you guys use very rigorous in-house testing procedures on your subs, none of which I would find to be realistic, I guess I find it just as relevant then as Johns T/S testing if not more. I mean how much was that linear laser testing machine that you guys use? You have gone into detail on other testing procedures before but I can not recall them at this time, but you and I both know that its kind of weird to call John out on his testing procedures when FI/AAs are just as(if not more) lab oriented.

Right, we do have a TON of technical stuff that we examine, but notice we don't preach to the choir about it? Because we do know what is going on, we do know what the cone is doing, we do know what the spiders are doing, we know where flux is going and where it isn't, but we do not put out the laundry list of data and white papers all over the place to try to prove a point to get people to buy something because of technical data. We don't go out and say yeah we changed this glue joint because we found that it was more prone to failure at this given rate so you need to buy these now. We didn't even announce the coming of the 11.25" motor, nor any of the iterations that has changed of it since the beginning of that run. It just is what it is at the end of the day, because it is for music and what the end user is wanting to listen to.

I also never said that a BTL will sound like that sub will..it obviously won't, it is waaaaaaaaaaaaay overbuilt and not meant for the same target as the AV (obviously). If you would want to compare an apple to an apple that could be arranged. What is done in house has everything to do with what goes on in a car. Have you ever taken a voice coil out of the case, hooked it up and measured current/voltage that you could apply to it without blowing it while sitting on the work bench? That shows the sub is playing a ultra high frequency and not moving therefore not cooling, you record that data and see how long it will take a given wattage until glue out gasses swells the former and the wire pops like a fuse. Then you know exactly at what point it thermally fails and you make note of it on x layer coil, y guage wire, z height, it will take this much wattage at 1000Hz not moving. Then you go into square wave, note how voltage and current changes, also note how heat changes in the coil and how it fails much quicker. Then you go into .35 ohm, .75 ohm, 1.5ohm, 3ohm, 6ohm testing and note how the current vs. voltage effects failing points at a given nominal 1000 watts of input power. The coils with more current going through them out gassed much sooner...versus the coils with more voltage going through them (higher impedance).

What I would do to prove the point:

Take 2 of those Lambda motors (Which I love btw, fantastic design), the same everything minus the coil. Wind a set of coils with a inductance that is double what the other is and see if you can honestly hear the ~2ms in impulse delay that is there. If you can honestly tell a difference (i know other things are going to change) in response/delay in the vehicle I will be thoroughly impressed if you can even detect it. Simply because in your 4 runner for example your group delay of the waveform that the speaker is creating to your ear is going to be in the 10-12ms range. Keep in mind you have to do this blind and the person that is listening can't know what woofer is what and see if they can detect it. The only way to confirm the person can or can not tell a difference is a Mic array spaced every 6" all the way up the center of the car at ear level, which will require probably 30 DAC channels to record the data as the wave form passes by and the human subject will have to note which one he could tell a difference in, if any. We did some work a while back with identification of where a bullet was being shot from with an array like this on a kevlar helmet...the GUI language in that program was asinine.