Probably a stupid question, but I'll ask it anyway! I have an existing HD box connected to a Samsung R74 with no surround system, but want to replace the TV with a Sony 40D3000 + Sony home cinema system (DAVDZ630 or 830?). Would I need to connect the HD box to the amp via optical cable, or is it sufficient to connect it to the TV only via HDMI and let the Sony units sort out the surround sound? If I need to connect it to the amp, obviously I will have to buy one with an optical in, which pretty much steers me towards the DAVDZ830 (at £150 dearer than the 630). Thanks in advance for any advice.