That Cirrus DSP chip is what decodes the Dolby Digital and DTS streams. It's what the processors do with that data after it is decoded that separates them from one another. Lexicon's strength is their Logic 7 matrix decoder which does an incredible job of converting 2 channel material into a very natural sounding multi-channel presentation. It also expands on 5.1 sources and (on the MC-12) 6.1 sources. On top of that, they continue to refine Logic 7 constantly.

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Sanjay