I agree with what Prosenjit said.. From whatever I ve learnt and experienced so far middle order AVRs are under powered for BnWs and on top of it 683s need better power like a dedicated Stereo integrated if not a POWER amp connected to your AVR.
Thanks you both,
the thing is that I have that YAMAHA at home, and now I am wondering which speakers will be much suitable for it....what about WHARFEDALE Diamond 10.7?
Unless you still bent on going for B&Ws and feel that your pockets can be further lightened then you can always add a power amp , But other wise always suggestive to go by the room size and also Yamaha RXv Series is a bit on the brighter side so suggest speakers with a bit warmer signature..