That's a good point, the Pre-5 dos not have any signal processing capability at all, no bass/treble control, not even balance. That means your digital source(s) has to be able to handle all of the processing. So if you're listening to a DVD-Audio disc, the player has to decode the MLP encoding, apply time alignment, set each channel level, apply bass management, do the D/A conversion and then output a high quality analog signal from the 6 channel outputs. A lot of DVD players don't do all of that. They may be able to set channel levels, but not do time alignment or bass management.