I am buying my first home surround system. I belive i wil go for B&W speakers (602 S3 front, 303 back and LCR 60 center), together with Yamaha 630 or Onkyo 600 receiver. I think i will wait a bit with a subwoofer. Are all of this speakers magneticaly shielded? Will be the system without subwoofer still OK with the mentioned configuration? Are this two receivers ok for this speakers? Thank you for all your advices.