<font color='#8D38C9'>Yeah, the marketing guys love to say stuff like that!
But the engineers had their thinking caps on. ALPHA24 is basically upsampling with interpolation. I'm not an engineer (maybe one of the AH staff can do better than me, here) but they basically add dither and perform calculations on the data to extrapolate 24 bits. I don't understand the math involved, but while they don't really make *much* new information, this allows more accurate processing of the Least Significant Bit which increased perceived low level detail retreival (in a linear PCM system, the signal is most accurately represented at high levels, most problems occur with low level signals represented by less bits).
True upsampling doesn't attempt to add any information, while interpolation actually speculates upon/extrapolates from what is there what should/could be there. That might sound sorta dicey but it's a highly effective technique. Perpetual Technology is one well known proponent of this technique that's legendary for the performance of their digital engine.
Not long ago the technology used by Denon in their ALPHA24 was unattainable for any sane amount of money.
But, as with all things audio, opinions vary. Many swear by upsampling but some don't like it. There's a growing camp of audiophools that don't even like the oversampling that most digital systems use; non-oversampling DACS like the Scott Nixon TubeDAC & Chris Own's dACK! have legions of fans.
As with all things, listen for yourself and make up your own mind. I like Denon & ALPHA24, but it's not like they're gonna give me an commission for talking anyone into buying one!
Sorry if I misunderstood you Ross, and I wasn't trying to be a ####! I thought you meant the 03 & 05 weren't different: my bad. And I've never been to a Circuit City- they don't have 'em in my part of the country and I don't know what they sell.
I still wonder, though, under what circumstances you made the comparison. Although I agree B&M stores are nice (return policy, warrenty & the chance to evaluate build quality, for what it's worth), a brief audition in a retail environement is a pretty poor way to accertain the merits of a component. Beats guessing, I suppose!
As I've said, it's no skin off my nose whether someone buys one brand or another. I'm only suggesting if you get the chance to try it under good conditions (hopefully/ideally in your own system with music of your own choosing) it's worth trying out for yourself.</font>