In reviews and articles I've read for certain external DAC's like V-DAC or DacMagic, I've noticed the reviewer mention he tried the DAC connected to different CD players and had different results. It was my understanding that when a source is connected via digital out, that it is just that. A source. If no digital to analog conversion goes on in the source, than why is does the DAC sound different when connected to different sources? To save money, I was going to buy an external DAC and connect all of my current electronics to it (computer, DVD player, DVR, etc...) I don't have cheap electronics, but they're certainly not top of the line. Does connecting the external DAC to a cheap piece of equipment defeat the purpose of having the expensive DAC, or is it still worth the money to do so?