Focal Kanta No.2

You can also look at the NRC measurements for the Sopra 2 and see that Focal's figures don't correlate at all with Focal specified frequency response for the Sopra 2. That test is in the NRC chamber and you can see crossed response the steps into the port response and requires room reinforcement. Stereophile had indicated the larger Sopra 3 had its port tuned to around 32hz. Based on the NRC chart, the Sopra 2 is around 36hz and I would likely guess the Kanta could be around 38hz port tuning due to its slightly lesser specification as compared to the Sopra 2. The takeaway is simple, The Sopra 2 or Kanta 2 aren't full range designs and neither are they meant to be. The Sopra 2 does have decently low distortion at pretty honest 90db. The tweeter does lose linearity at 95db. I would expect distortion would be increasing anything above that level. Look at the distortion the NRC recorded for the Sopra 2 at 95db, it doesn't rise to appreciably from the bass drivers. I consider this to be a good design choice as you really don't want it to muddy the mid bass and lower mids. Now look at the Kef Reference 3 at the NRC. They decided to permit their small drivers to push just a bit lower than Focal had. When pushed at 95db, the distortion levels rise notably above what the Sopra 2. I prefer the Focal design route here in not pushing a smaller driver further than need be. The Sopra 2 distortion ends well below 200hz, the Kef Ref 3 end just shy of 400hz.  Kef had done a better job in keeping the mid and tweeter driver in terms of linearity and distortion, but the Sopra does have a wider dispersion in most the the usable audio band. 

Now lets be honest hear, Focal's spec sheet is lacking just like every manufacture throughout the speaker world. Also, not a single speaker designer on the planet will attest to 6.5" drivers being able to appreciably reach full range response without significant distortion of driver itself, or any driver in production at least. To engineer drivers that possibly could might take half the cost of the speaker given the use of four in a stereo pair. The spec sheet is a rough guide, but none are a gold standard as every maker knows that they need to market any product in the best light possible, even some notably fudging with the numbers to get there.

If you want to see some impressive NRC figures, the Magico S5 is superbly impressive in the bass area. The tweeter distortion is also great, just not linearity. He has seem to made some strides since then.

I will give the Sopra 2 a nod for being one of the better speakers at its price point. Even the Sopra 3 is pretty damn good at its point and I would say the Canton 3K the nod for best competitor to the Sopra 2. The Kanta 2 is well priced in Europe, just not here. The Contour 60 is quite the opposite being nine thousand euro and ten grand here. I consider the Kanta slightly expensive in the US, but it does have the best aesthetics of any of the close competitors.  The Kanta 3 might very well be the overall ticket since I'm not very appreciable to the stature of the Contour 60. The Magico A3 seems interesting, but a certainly a very plain looking box. The listening later on shall tell all.

Who’s NRC??? The ONLY accurate way to measure a speaker’s bass response is in free air. Even the best anechoic chambers create boundary reinforcement. That’s why JA at Stereophile does his measurements in a field. And his measurements of virtually every speaker he’s tested agree with Focal’s specs generally within the margin of experimental margin of errors.
What's more, getting clean 30Hz response from a 6.5" driver is hardly impossible. I have no doubt the Kanta No.2 can do it.

All I can say is that the Kanta No2 has one of the most natural and realistic bass presentations I’ve heard.  Strings also sound very much like the real thing.  Overall they deliver a very authentic reproduction of the source.  Not overly zingy or exaggerated in any frequency range...great scale and soundstaging with oodles of ambient detail.  I’m very pleased and I would say that pricing is commensurate with the competition.  I can also verify that deals can be had on most speakers if you shop around!

The NRC is a Canadian measurements lab for speakers with NRC standing National Research Council. It was developed by Dr. Floyd Toole, who even JA would refer to as one of the people who defined loudspeaker measurements for modern speakers and currently is employed with Harman Corporation. Harman has a more advanced development of what he started at the NRC. John Atkinson has referenced Dr. Floyd Toole in his own documents on loudspeaker measurements.

Also, look at the NRC charts that Soundstage has published. In the more than fifty speakers measured with 6.5" drivers, not a single unit was able to produce 30hz cleanly without appreciable rise in distortion. It may be negligible at low levels, but it quickly rises above 80db. Could it be done? Yes, I believe it can be made with some extremely expensive materials. I run an FEA lab used for a certain disciplines of engineering and I can tell you about materials that cost is beyond the budget of most loudspeaker implementations. The other factors would pertain to the motor structure in the former, magnet structure, the coil would have to be very high power handling to have extremely long excursion. The surrounds require some impressive roll as well not to mention the spider.

In fact, Focal themselves have pioneered technology into production that does address a number of issues in their EM series drivers, which replaces the permanent magnet with an EM instead. This would allow the motor to reach the excursion required without extreme power loading. If stanene (very new material that holds huge promise) wire would be used, it could really create an incredible powerful motor/field structure. The cone would still require additional rigidity or more of them to spread the load and the suspension would still be a possible issue, but maybe if you implemented suspension via EM with the ability for the former to have a rest position when off, it might work out. Build the former and cone into single solid piece while reinforcing cone. But this wouldn't be in the budget of the Sopra line unless the driver in question went into volume production. I mean tens of millions per year of the very same driver.

I know, its a great deal of techno babble when all you need to is to use larger cones drivers to get there for much less cost. Old engine line, no replacement for displacement. Well, that isn't true any longer and it could possibly be true in speakers at some point. Just not today.

@mmeysarosh 
The only difference between the woofers in my 936's and those in the Kanta No.2 is the motor. They're specifically designed to be more linear at longer excursions. 

But again to my point: there's very little going on in the vast majority of music that needs extension much below 40Hz. A speaker with a low point in the 30's doesn't require a sub in a typical room unless you're absolutely obsessed with overblown bass. The one issue I'm always hearing and reading about with speakers that have active bass systems is that they sound unnatural and require constant adjustment. Given a choice between Kanta No.2's and Golden Ear References, I'm taking the Focal's all day long just because they'll always sound more natural.