Did someone ask for an engineer? Haha! I hate to be non-specific, but every link in the chain counts at some level, and they each have a quantifiable effect on the sound. Will I spend a ton of money on solid gold cables? No. But a good recording, a good amp, and good speakers are important. Every link you add in the chain increases the overall distortion exponentially, and you can quickly multiply distortion to audible levels.
Let's talk about DAC's - at their simplest, they can be very cheap and not so good for a number of build-quality related reasons. It's not too complex to build a good one and I think it's possible to find one that passes the signal with minimal distortion at a decent price. It doesn't take much power to put out a 1v line, but if you have inferior components, you can still mess up a decent DAC.