Overpeck, Please explain this too me...

[Alaxan 5,000+ posts]

Mat I would like to say a few things. First and foremost...I have no problem with your company or product. I have been doing a good deal of research here and looking into it so see exactly everything that has been going on. I do see that you are hardworking individual however that is trying desparately to promote your product and perhaps going about it in the wrongs ways as far as some people see it. I have spent a great deal of time on this and would love to be able to work something out so an independent review of your product could be done by myself in coexistance with a few others. In all fairness if you are going to promote your product in forums like this it should be expected to get nailed from one side to the other it would also be fair to allow those higher members of those forums a chance to review the product. We have been working on the idea of taking a collection etc.. for this, but any help from you would be greatly appreciated as well. I have been in the caraudio field specifically for the last 12years and feel that if there is going to be a co-existance here that something has to be done at the least to make a final statement to the members of the forums you are promoting in.

 

[jlaine 10+ year member]

Originally posted by Matt Overpeck We NEVER threatened anyone...about anything (what utter nonsense). But there is one extreme source for that kind bizarre of dribble...

 

We did suggest to one nit-wit that if he should refrain from making false allegations that we "stole" (that was the word used) our technology from another company (because there is a term for that -- and it is NOT protected by the First Amendment). And he promptly shut-up...end of story.

Actually, derek just got louder... he never shut up for you... //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Originally posted by Matt Overpeck And as far as the accuracy of our specs, the EVO-R test that has been purported to show that we are not accurate in our Xmax specs, only shows that the rearward travel of the suspension is not as it should be (likely due to a spider with excessive resin on it). So this impacted the X-MAX number.

Thought the coil was glued too far forward? So both units you sent to them managed to be identically off?

Originally posted by Matt Overpeck However, as with EVERY other EVO-R test report over the past year, the Xmag (which is really the most important thing in looking at the linear capability of the motor) was still 25 - 26 mm. This is well within a 10% tolerance for production units, vs. our published specification of 27 mm.

How many EVO-R reports are we comparing here? The singular displayed DUMAX test?

Remember matt, we were talking Xmax rating, not Xmag.

Originally posted by Matt Overpeck By the way, then the JL 12 W7 was tested, it failed to meet it's published specification by 10% (26.2 DUMAX measured vs. 29.2 published X-MAX). So we are hardly guilty of having committed any transgressions.

JL's production tolerances: tested 26.2, stated 29.2, 10% variance

Audiomobile's production tolerances: tested 20.7, stated 27.xx, 23% variance or more...

Originally posted by Matt Overpeck And the recent test of the EVO-R 2315 showed that the Xmag (linear motor travel) and the Xsus (linear suspension travel), which are independently tested, BOTH were 28 mm (though the unit sent for DUMAX testing was a proto that unfortunatly had the VC offset by a huge amount. Properly centered (even off by just half a s much, would have resulted in the spec being met. So this just further illustrates that the product will perform as advertised.

How do you intend on testing this? You don't build the driver, how can you manage QC on something like the VC being offset like this? You can't tell me your measures of checks and balances at your warehouse take this into account... Either a design flaw, or you need to have a serious discussion with TC Sounds on their construction of your drivers...

For that matter, why were both samples sent to ME off by the exact same amount...

Originally posted by Matt Overpeck So while some do not understand the actual technical aspects of what DUMAX numbers mean, let's just say that the linear behavior of the suspension is FAR less important then the behavior of the motor (as it the VC exiting the gap, that determines the onset of audible distortion).

 

Hope that clears a few things up....

 

Cheers!

 

Matt

 

Audiomobile

Help me on this one.. You actually believe that the onset of audible distortion is once the VC exits the gap?

You cannot be serious... Such a blanket statement is nothing short of foolish...

 

[RangerMan Premium Member]

Originally posted by Matt Overpeck We NEVER threatened anyone...about anything (what utter nonsense). But there is one extreme source for that kind bizarre of dribble...

 

We did suggest to one nit-wit that if he should refrain from making false allegations that we "stole" (that was the word used) our technology from another company (because there is a term for that -- and it is NOT protected by the First Amendment). And he promptly shut-up...end of story.

 

And as far as the accuracy of our specs, the EVO-R test that has been purported to show that we are not accurate in our Xmax specs, only shows that the rearward travel of the suspension is not as it should be (likely due to a spider with excessive resin on it). So this impacted the X-MAX number.

 

However, as with EVERY other EVO-R test report over the past year, the Xmag (which is really the most important thing in looking at the linear capability of the motor) was still 25 - 26 mm. This is well within a 10% tolerance for production units, vs. our published specification of 27 mm.

 

By the way, then the JL 12 W7 was tested, it failed to meet it's published specification by 10% (26.2 DUMAX measured vs. 29.2 published X-MAX). So we are hardly guilty of having committed any transgressions.

 

And the recent test of the EVO-R 2315 showed that the Xmag (linear motor travel) and the Xsus (linear suspension travel), which are independently tested, BOTH were 28 mm (though the unit sent for DUMAX testing was a proto that unfortunatly had the VC offset by a huge amount. Properly centered (even off by just half a s much, would have resulted in the spec being met. So this just further illustrates that the product will perform as advertised.

 

It is worth noting that the EVO-R also SMASHED the SPL output for in-car SPL, both with low-distortion (test tones from 25 - 62 Hz.) as well as in peak SL output, by 2 - 3 dB!!! (and did this in only a 1.5' sealed box -- same as that used to test the 12 W7).

 

The EVO-R tested in-car could not have bested the numbers put up by the JL 12 W7 by such a huge amount (2 - 3 dB), UNLESSS it had comparable Xmax. As the difference in the cone area would amount to 2 - 3 dB, but ONLY if the linear excursion is similar.

 

And the EVO-R also had a flatter frequency response (1.8 dB tolerance), down to 10 Hz.! If you put that sub in a 33 - 50% larger box, then it would have added another 2 - 3 dB output under 25 Hz. Larger boxes result in more output in the bottom octave.

 

So while some do not understand the actual technical aspects of what DUMAX numbers mean, let's just say that the linear behavior of the suspension is FAR less important then the behavior of the motor (as it the VC exiting the gap, that determines the onset of audible distortion).

 

Hope that clears a few things up....

 

Cheers!

 

Matt

 

Audiomobile

Excess resin??? Your losing you touch Matt...

 

[KoBan715 10+ year member]

I cant take anymore of his BullSh1t.

 

[bumpin_blazer 5,000+ posts]

wow now i can say jlaine has honest hatred towards matt overpeck although who can blame him.

adam

 

[lilflop04 10+ year member]

where ha stated this? he simply stated facts.

 

[kaosmoon 10+ year member]

w7 is rated by overhang I believe. Manville explained plenty of times I believe on carsound. JL rates everything that way (If memory serves correctly at least for subwoofers). At least that's a consistent way of doing it. Some drivers meet or excede their overhang. I guess it just happens. They don't do dumax measurements (and market as such), then have different dumax measurements, and then have different results. Educating folks on the net is difficult sometimes about dumax testing, how to read the results and so on, Can you possibly imagine JL Audio bringing that into shops all over the world and having them try and explain to them DUMAX. Honestly for me, that's one big reason I see no problem with it.

One is a physical spec (physical spec performing differently as tested but still advertised as a physical spec and not actual measurement doesn't really seem too horrible), one is a measured tested spec(using that tested spec to move woofers, having it retested and falling short), big difference imo. My opinion on the matter really isn't worthwhile though.

Evo-R is still a darn cool woofer and I'm sure one will make its way through my car sooner or later, The whole debate seems a little sided on the woofer can't be good becuase it doesn't do this or that. I think the only problem people are dwelling on it Matt is just simply to russle you up.

Ben

 

[Corsica 5,000+ posts]

Matt I personally have no beef with ya. Your speakers seem to have some problems with XMAG etc. but thats can happen from tym to time. Personally i would like a chance to review a sub of yours no matter which sub it is. I just would like to see your company in action and around here i see nothing of that.

J