In my experimentation and experiences over several decades, those equipment pieces that do the transduction are the most critical for sonic quality. Turntable/arm/cartridge, CD/Player/transports and speakers come to mind. for me as having the most-significant effect on sonic quality. Of course, EVERY piece that touches the digital or analog signal will affect the sound. It's just degrees of it in my opinion. One other important aspect of listening is the listening-environment ! Much over-looked, it can make the difference between happy listening and frustration. Make sure you take care of your acoustics ! Most likely the least-expensive "component" change you can make for significant sonic accuracy...