Again, I am looking for a smooth sounding system without bloated bass, harsh highs or very prominent or "forward" midrange.
Keep in mind that it's your choice of speakers, more than anything else, that will govern this. You can buy awfully cheap electronics today that entail relatively little sonic compromise, so budget according. As for speakers, to each his own, but be sure to include in your comparisons one or more of the following brands: Energy, Paradigm, PSB, Infinity, JBL. These are all companies with a very particular approach to good sound (and some solid research behind it) that makes a good standard against which to judge the rest of the market, especially in the budget category.
I'll second the Technics turntable recommendation above. It's not high-end by any means (and definitely upgrade the cartridge), but it's a p-mount unit, which means it'll be easy to set up (good for a kid), and it won't trash his LPs--so he'll still have them to listen to when and if he decides to upgrade.
Finally, as the guy who started the "ask your son" trope, let me say that it wasn't my intention to give you a hard time. It's just that we regularly see posts about what to buy/recommend for a "friend," which turns out to be an exercise in foisting one's own hobby/priorities on somebody else. I meant to warn you away from that, though your follow-up post suggests you weren't falling into that trap. My apologies for any suggestion otherwise.
