the 6th channel will add very little over two good 4th and 5th channel speakers. why wouldnt you go for 7.1 instead of 6.1 in the first place though? not that 7.1 is much better than 6.1, but what are you going to do with/get 1 speaker? if you upgrade in the future you dont want one oddball. 7.1 is for larger rooms, because it gives a broader sound stage, 6.1 does this to an extent but is more for the very rear sounds. tripole/dipoles achieve that sound very well anyway, so the point is moot. if you were going with standard bookshelfs for the rears, then you would see more of a difference, but with tripoles, its a waste of money.

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