It's common knowledge that as you move up the audio food chain, digital audio sounds better. Trying to make a statement about all digital audio systems based only on a single sample of a relatively (by high-end audiophile standards) low price/performance component is meaningless.
The OP too general a term "natural" is not an absolute, but a subjective judgement. For instance, as one moves up the digital audio food chain, there will come a point where some will say it sounds "natural" while others would disagree. Also, how would I know if we injected some "tube magic" into the digital audio chain whether it would satisfy the OP "natural" requirement?