Focal Kanta No.2

It actually is an absolute direct correlation and proven through both computational FEA and measurement. You get a substantial area in increase when moving from six to eight inch cones and this allow substantially reduced excursion and pressure exerted on the cone to achieve similar amplitude at lower bass frequencies. So while the shorter cone is stiffer due to its smaller size, its generally a linear gain unless shape is changed, which it usually is in most cases. The force increase on the other hand is a non linear function as there are multiple factors at play, the pressure itself and increase in cone velocity and acceleration in air. A smaller driver will always requires more energy to achieve the same output as larger driver in low bass area. An eight inch cone offers about fifty percent more area than a six and half inch cone. Now as that cone gets larger, the ability to achieve the rates of acceleration at higher frequencies becomes overly challenging. Not to mention the dispersion beaming that also occurs, which a six inch cone begins to beam at around 2khz, maybe slightly less. I'd do believe there would be artifacts if the wavelength produced becomes larger than the cone, but I'm not sure if its of any issues at the sized being discussed.

In ending, there isn't a single part of the driver that wouldn't require significantly more buildup if wanted to achieve a similar lower frequency performance without distortion increase. It might even be easier to use Focal's own EM technology to achieve what your proposing, but at a notable cost. Going to a larger cone is simply much more cost effective and negative is mainly overall size and increase in baffle if front mounted, a negative if trying to increase dispersion width but can be addressed with baffle shaping.

@mmeysarosh 

Yeah, that's always the apples to oranges argument that gets made. Well duh, moving less air is going to produce less amplitude. So you use several. I really don't feel like crunching the numbers at 5am with my contacts out, but I have done the numbers and the 3 6.5" drivers I'm listening to roughly equal the area of a 10 inch cone. So seeing as how they move the same volume of air as a 10 inch driver, their excursion is identical while still enjoying the benefits of the stiffness of the smaller cones. No distortion penalty due to excursion. 

That is an rather myopic view of engineering of any mechanical system. You're comparing three motor system which will in combination require more power than the single driver. The cabinet and baffle construction will be more complex and costly and the bass performance of each driver will vary due to mechanical acoustic properties as they won't have identical operating environments in the cabinets. You do get some advantages, but those don't outweigh the complications. Even if you increase cabinet volume, you introduce cabinet anomalies if not properly braced and damped.

Using an array of smaller drivers is a solution, but I wouldn't consider it optimal application unless the room size is small, which you had mentioned is your current setup. In my room, which is more than double what Focal specifies for the 936 and still significantly more than the Kanta2, going to larger cone diameter is the best route. In my case it works ideally with two eight inch drivers, but a single twelve could do as well. The negative to the twelve is wide baffle and cabinet construction to contain two eights are reasonable in engineering and cost. Right sized tools for the job is always best. 

It's not that myopic at all. I've heard the argument that all those individual sources can be identified, but the physics don't reflect that. If you're argument was correct, the 948's would require less power for a given output in the bass region, but the require more using fewer, larger, but otherwise identical drivers. The physics of the system suggests that the drivers mechanically couple as roughly described by line arrays theory and deviations tend to nullify, not amplify.