Again, it's not so much that the music sounds "better" in Rondo (production-wise and arrangement-wise, I feel DXC does a better job), it's just that it has that classic 1993 "first ever CD-ROM Castlevania with Redbook audio" sound to it and I like that element. To put it another way, it's not that I prefer Rondo because it doesn't feel aged or because I feel like anything is particularly "better" about it - I like it because it does feel aged and I guess I hear some ambition in it of Konami reaching for the stars for the best Castlevania ever while still using that humble hardware (the PC Engine).
It's a little like hearing a child get better and better at playing music...but then there's that one day when you hear him play something and even though he could obviously be better, there's something in that performance where you can tell he's destined for great things ahead. That's what Rondo was for Castlevania - It was the series' first outing on CD media and demonstrated clearly that even in the new frontier, Castlevania was still a force to be reckoned with well into the future.
That spirit just isn't captured in DXC for me. It looks -too- polished and with -too- high of production values. There's no more ambition for the future, just "modernizing" an old game for a quick buck in the present. It looks, sounds, and feels really good and was done well, but it also feels somehow cheap.