Jitter is reduced or eliminated with a proper clock mechanism. In my opinion, most DACs suffer from something that most of you are aware of for pre-amps but don't apply to DACs and that is the power supply. most internal DACS have a mediocre power supply and therefore the system reponse in inadequate compared to external DACs. Although I have seen external DACs that have terrible power supplies also. Most DAC manufactures are great on the digital side but totally are lost on the analog/power supply side. Look at the major, realy great DACs out there and you will find a really high-end heavy duty power supply inside. Which is not shared with all the other stuff inside a CD player. I was sold on external DACs long ago when I compared several CD/DVD players using analog output and then ran the digital output to some really good heavy duty external DACs. Not even close. external DAC/CD transports won ever time. My advice, go borrow a really decent used DAC like a Theta DS Pro Gen Va and run your existing CD player's digital output into the DAC, then into your pre-amp, and also run the CD player's analog out into the pre-amp also and A/B compare them. you will hear an amazing difference.
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