I have no technical answer. But for sure we can't call this a DSP or room compensation technology like we have today in BL50 and 90, and in different brands, for which i am totally convinced of the necessity to get the better of any speakers for music listening. 

Given the position of the microphons on the BL5, even if the calibration is running different frequencies, it has 90% impact on the bass only. To me it is just like a sophisticated switch for ABL to replace the manual one we have on all Beolab speakers to adjust the bass level depending if the speakers are Free, against a Wall or in Corner position. Not much more, but maybe I am wrong. Anyway the result is this one to me hears.

oli wrote:

Given the position of the microphons on the BL5, even if the calibration is running different frequencies, it has 90% impact on the bass only. To me it is just like a sophisticated switch for ABL to replace the manual one we have on all Beolab speakers to adjust the bass level depending if the speakers are Free, against a Wall or in Corner position.

I was thinking the same.

If it would correct the complete audible frequency spectrum, then there should have been a mic on top, wouldn't that be?

But why drives the BL5 then a test signal from the lower bass upwards to the tweeter? Still curious what happens inside the BL5. Especially when you think about the realtime equalizing which causes delay and phase-shifts, but at the end the music has to be in phase with the rest of your setup.