Originally Posted by sdurani
There's no question that discrete multi-channel has the potential advantage over matrixed surround, but in actual use some mixes may not be making full use of those advantages. As others have mentioned, dialogue can be copied to all front channels, there could be very little surround activity, the mix could sound like 5 mono pools of sound instead of a cohesive ring around the listener with imaging between speakers, etc.
In those instances, downmixing the discrete multi-channel mix to stereo and then extracting back the centre and surround channels can have advantages. Since no matrix extraction is perfect, small amounts of leakage between channels can cause the soundstage to appear more blended with noticeable phantom imaging between speakers, while a little bit of leakage into the surrounds can yield greater envelopment.
It's a situation where minor flaws of an older technology sound preferable to sub-optimal use of newer technology. Well, "sound preferable" to some people. I've seen examples of this with warm, lush tube amps vs cold, analytical-sounding solid state amps. In this particular case it is matrix surround vs discrete multi-channel, where the former has the added advantage of using the same matrix encoder (Logic7) for downmixing as it uses as the matrix decoder (Logic7) when extracting the centre and surround content.
Keep in mind..
That for the HK products with the more powerful TI DSPs (DA710 x 2), its Logic 7 actually can take a 5.1 DTS Master Audio or Dolby True Audio native
stream and post-process
with Logic 7. Here Logic 7 is applying some unique filtering and steering, I won't say the end-result is better or worse
But many, many listeners prefer this DSP post-processing mode.
Note that we have known Dr. David Griesinger (inventor of Logic 7) for many, many years and have been truly impressed with his creativity and sonic performances.
Just my $0.02...