I'm now confused about these new formats, I had set out to buy a replacement 5,1 amp on the grounds there is no physical way I can add any more speakers in our small living room!!. Now the Pioneer VSX-D711 offers DD, DTS, DPLII and 'Virtual 6.1', and the Yamaha DSP-AX630SE offers DD, DTS, DPLII, Dolby Digital EX and is 'DTS -ES compatible', is the Yamaha just offering more than I need and I should save my money ??. What is 'discrete' is this another way of saying virtual or something completely different ??