I have a new Z87 board from AsRock with "Purity Sound", to quote "Realtek ALC1150 audio codec, 115dB SNR DAC with Differential Amplifier, TI® 5532 Premium Headset Amplifier which supports up to 600 ohm headphones, cap less Direct Drive technology, EMI shielding cover, PCB isolate shielding and support for DTS Connect". While this sounds fine on paper I find that the 5 old Xonar DX still has an advantage, like the article mentions, the onboard solution is simply lacking in lows and highs, there are some nuances of the sound that are lost in both "gaming" grade headphones and MOSFET amplifier with speakers. Audiophile headphones make this difference even more noticeable. But this is to be expected if you look at the Xonar DX board vs. the onboard solution: you immediately notice that there are more filtering caps, beter DACs (even though the front one is listed at 115 dB SNR and the other is listed at 110 dB SNR), better opamps, relays that physically decouple inputs/outputs etc.
What I suggest to Mr. Matthew DeCarlo is to try out the Xonar without enhancements, by pressing the HiFi button in the audio center, I find it way crisper compared to any of the DSP stuff. The DSP works fine on cheap audio solutions like onboard audio or not-so-good phones with earbuds but I find it that they hurt quality on good audio solutions with good headphones/speakers.
As a sidenote, what I find amazing is the number of people that "like music", have tons of audio, listen to it a lot but really have no idea about how it should sound. As always, ignorance is bliss: as long as you do not try something superior you do not know what you miss and what you should expect.