Strangely, these are very different speakers indeed in my opinion.
I liken the BeoLab 9 to a BMW 325i. You know it has some power and it can handle itself perfectly well - so you don't really expect too much. You rarely need to thrash it - as it does everything very well indeed. However, you don't thrash it because it's a 325i - you kind of respect its limits but are suitably impressed with its 6-Cylinder smoothness and grunt.
However, the BeoLab 5's are like an M3.. You get in and expect to be wowed from the very moment you turn the key, with blistering acceleration and a howling engine - but you're kind of disappointed initially. It's better than the 325i, no doubt - but what's all the fuss about?
Then.. you floor it. It just revs, and revs, and howls, and howls even louder - then the smile spreads across your face. THIS is what it's all about.
This, gentlemen, is the BeoLab 5. You don't realise what you've got until you press the pedal into the carpet, then it all becomes apparent what the fuss is about.
Lee
PS - BeoLab 5 owners will know what i'm talking about 
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